Questions · Page 2 of 5

M.C.Q. [1 Marks Each]

MCQ 511 Mark
If the sum of two consecutive multiples of $2$ is $18,$ then the numbers are:
  • $8, 10$
  • B
    $6, 12$
  • C
    $5, 13$
  • D
    $4, 14$
Answer
Correct option: A.
$8, 10$

Let the multiples of $2$ are $x$ and $x + 2$
Given, sum $= 18$
$\Rightarrow x + x + 2 = 18$
$\Rightarrow 2x + 2 = 18$
$\Rightarrow 2x = 18 - 2$
$\Rightarrow 2x = 16$
$\Rightarrow\text{ x} = \frac{16}{2}$
$\Rightarrow x = 8$
So, the numbers are $8, 8 + 2 = 8, 10$

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MCQ 521 Mark
After $12$ years, Ram will be $5$ times as old as he is now. Then the present age of Ram is:
  • A
    $2$ years
  • $3$ years
  • C
    $4$ years
  • D
    $5$ years
Answer
Correct option: B.
$3$ years
Let the present age of Ram is $x$
Given, after $12$ years, Ram will be $5$ times as old as he is now.
$\Rightarrow x + 12 = 5x$
$\Rightarrow 5x - x = 12$
$\Rightarrow 4x = 12$
$\Rightarrow \text{ x} = \frac{12}{4}$
$\Rightarrow x = 3$
So, the present age of Ram is $3$ years.
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MCQ 531 Mark
What is $y$ in $10y - 20 = 50?$
  • A
    $5$
  • B
    $9$
  • $7$
  • D
    $2$
Answer
Correct option: C.
$7$

$10y - 20 = 50$
$\Rightarrow 10y = 50 + 20$
$\Rightarrow 10y = 70$
$\Rightarrow\text{y} = \frac{70}{10}$
$\Rightarrow y = 7$

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MCQ 541 Mark
If $x = 2,$ then the value of $\frac{(1 - 3\text{x})}{3} $ is equal to:
  • A
    $\frac{-3}{5}$
  • B
    $\frac{3}{5}$
  • C
    $\frac{5}{3}$
  • $\frac{-5}{3}$
Answer
Correct option: D.
$\frac{-5}{3}$

Given, $x = 2,$
Now $\frac{(1 - 3\text{x})}{3} = \frac{({1-3\times2)}}{3}$
$= \frac{(1−6)}{3}$
$= \frac{(−5)}{3}$

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MCQ 551 Mark
Which of the following numbers satisfy the equation $-6 + x = -12?$
  • A
    $2$
  • B
    $6$
  • $-6$
  • D
    $-2$
Answer
Correct option: C.
$-6$
 
Let us put the values given in the options in equation $-6 + x = -12$
$a.$ Put $x = 2$
$\Rightarrow -6 + 2 = -2$
$\Rightarrow -4 = -12$
$\therefore \text{LHS} \neq \text{RHS}$
$b.$ Put $x = 6$
$\Rightarrow -6 + (6) = -12$
$\Rightarrow 0 = -12$
$\therefore \text{LHS} \neq \text{RHS}$
$c.$ Put $x = -6$
$\Rightarrow -6 + (-6) = -12$
$\Rightarrow -6 - 6 = -12$
$\Rightarrow -12 = -12$
$\therefore \text{LHS} = \text{RHS}( $satisfied$)$
Now, there is no need to check the next option.
Hence $, x = -6$ satisfied the given equation.
 
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MCQ 561 Mark
Number of sides of equation in simple equation is/ are:
  • Two
  • B
    One
  • C
    Three
  • D
    None of these
Answer
Correct option: A.
Two
There are two sides in a linear equations that is $L.H.S$ and $R.H.S.$
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MCQ 571 Mark
Power of variable in a simple equation:
  • A
    $0$
  • One
  • C
    Two
  • D
    None
Answer
Correct option: B.
One
Power of variable in a simple equation is $1. A$ higher power will indicate a quadratic or polynomial equation.
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MCQ 581 Mark
Two supplementary angles differ by $40^\circ .$ The measure of the larger angle is:
  • A
    $70^\circ$
  • B
    $80^\circ$
  • $110^\circ$
  • D
    $100^\circ$
Answer
Correct option: C.
$110^\circ$

Let the larger angle be $x.$
Then, the smaller angle $= (x - 40^\circ )$
As, the sum of the two supplementary angles is always $180^\circ .$
$\Rightarrow x + (x - 40^\circ ) = 180^\circ $
$\Rightarrow 2x - 40^\circ = 180^\circ $
$\Rightarrow 2x = 180^\circ + 40^\circ $
$\Rightarrow 2x = 220^\circ $
$\Rightarrow\text{x}=\frac{220^\circ}{2} ($By transposing $2$ to $R.H.S.)$
$\therefore\text{x}=1106^\circ$
So, the measure of the larger angle is $110^\circ .$
Hence, the correct alternative is option $(c).$

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MCQ 591 Mark
A child drank $250$ lit. on Sunday. On Monday he drank 650 liter. On Tuesday he drank $100$ liter. How much in all did the child drink$?$
  • A
    $950$ liter.
  • $1000$ liter.
  • C
    $850$ liter.
  • D
    None of these
Answer
Correct option: B.
$1000$ liter.
sunday $250$ liter. monday $650$ liter. tuesday $= 100$ liter. total $= 250 + 650 + 100 = 1000$ liter
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MCQ 601 Mark
Mark against the correct answer in the following:
The ages of $A$ and $B$ are in the ratio $4 : 3.$ After $6$ years their ages will be in the ratio $11 : 9$. A’s present age is:
  • $12$ years
  • B
    $16$ years
  • C
    $20$ years
  • D
    $24$ years
Answer
Correct option: A.
$12$ years
Let the ages of $A$ and $B$ be $x$ and $y$ years respectively,
Now, $\frac{\text{x}}{\text{y}}=\frac{4}{3}$
$\Rightarrow3\text{x}=4\text{y}$
$\Rightarrow\text{x}=\frac{4}{3}\text{y}$
After 6 years, We have:
$\frac{\text{x}+6}{\text{y}+6}=\frac{11}{6}$
$\Rightarrow\frac{\frac{4}{3}\text{y}+6}{\text{y}+6}=\frac{11}{9}$
$\Rightarrow\frac{4\text{y}+18}{3(\text{y}+6)}=\frac{11}{9}$
$\Rightarrow36\text{y}+162=33\text{y}+198$
$3\text{y}=36$
$\Rightarrow\text{y}=12$
$\therefore\text{x}=\frac{4}{3}\times12=16$
Hence, $A's$ present age is $16$ years.
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MCQ 611 Mark
The solution of the equation $5x - 8 = x + 4$ is:
  • A
    $-2$
  • B
    $2$
  • C
    $-3$
  • $3$
Answer
Correct option: D.
$3$

Given, $5x - 8 = x + 4$
$\Rightarrow 5x - 8 - x = 4$
$\Rightarrow 4x - 8 = 4$
$\Rightarrow 4x = 4 + 8$
$\Rightarrow 4x = 12$
$\Rightarrow\text{x} = \frac{12}{4}$
$\Rightarrow x = 3$

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MCQ 621 Mark
If $1400 \times x = 1050.$ Then, $x =?$
  • A
    $\frac{1}{4}$
  • B
    $\frac{3}{5}$
  • C
    $\frac{2}{3}$
  • $\frac{3}{4}$
Answer
Correct option: D.
$\frac{3}{4}$

$1400 \times\text{x} =1050$
$\Rightarrow{\text{x}}=\frac{1050}{1400}=\frac{3}{4}$

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MCQ 631 Mark
If $7x - 4 = -25,$ then the value of $x$ is:
  • A
    $\frac{-29}{7}$
  • B
    $\frac{29}{7}$
  • C
    $3$
  • $-3$
Answer
Correct option: D.
$-3$
Given, $7x - 4 = -25$
$\Rightarrow 7x = -25 + 4$
$\Rightarrow 7x = -21$
$\Rightarrow\text{x} = \frac{-21}{7}$
$\Rightarrow x = -3$
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MCQ 641 Mark
Mark against the correct answer in the following:
If $\frac{\text{x}-2}{3}=\frac{2\text{x}-1}{3}-1$, then $x =?$
  • $2$
  • B
    $4$
  • C
    $6$
  • D
    $8$
Answer
Correct option: A.
$2$
$\frac{\text{x}-2}{3}=\frac{2\text{x}-1}{3}-1$
$\Rightarrow\frac{\text{x}-2}{3}=\frac{2\text{x}-1-3}{3}$
$\Rightarrow\text{x}-2=2\text{x}-4$
$\Rightarrow\text{x}-2\text{x}=-4+2$
$\Rightarrow-\text{x}=-2$
$\Rightarrow\text{x}=2$
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MCQ 651 Mark
The solution of the equation $7n + 5 = 12$ is:
  • A
    $0$
  • B
    $-1$
  • $1$
  • D
    $5$
Answer
Correct option: C.
$1$

$ 7n + 5 = 12$
$\Rightarrow 7n = 12 - 5$
$\Rightarrow 7n = 7$
$\Rightarrow \text{n}= \frac{7}{7}$
$= 1$

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MCQ 661 Mark
The solution of which of the following equations is neither a positive fraction nor an integer$?$
  • A
    $2x + 6 = 0$
  • B
    $3x - 5=0$
  • C
    $5x - 8 = x + 4$
  • $4x + 7 = x $
Answer
Correct option: D.
$4x + 7 = x $
Let us solve the equation:
$a.$ Given equation is $2x + 6 = 0$
$\Rightarrow2\text{x}=-6 [$transposing $6$ to $\text{RHS}]$
$\Rightarrow\text{x}=-\frac{6}{2} [$dividing both sides by $2]$
$\Rightarrow\text{x}=-3($integer$)$
$b.$ Given equation is $3x - 5 = 0$
$\Rightarrow3\text{x}=5[$transposing $5$ to $\text{RHS}]$
$\Rightarrow\text{k}=\frac{5}{3} ($fraction$) [$dividing both sides by $3]$
$c.$ Given equation is $5x - 8 = x + 4$
$\Rightarrow5\text{x}=\text{x}+4+8[$transposing $8$ to $\text{RHS}]$
$\Rightarrow5\text{x}=\text{x}+12$
$\Rightarrow5\text{x}-\text{x}=12[$transposing $x$ to $ \text{LHS}]$
$\Rightarrow4\text{x}=12$
$\Rightarrow\text{x}=3($integer$) [$dividing both sides by $4]$
$d.$ Given equation is $4x + 7 = x + 2$
$\Rightarrow4\text{x}+7-\text{x}=2 [$transposing $x$ to $\text{LHS}]$
$\Rightarrow3\text{x}=2-7 [$transposing $7$ to $\text{RHS}]$
 $\Rightarrow3\text{x}=-5$
$\Rightarrow\text{x}=-\frac{5}{3} [$dividing both sides by $3]$
Which is neither a positive fraction nor an integer.
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MCQ 671 Mark
Two complementary angles differ by $20^\circ .$ The smaller angle is:
  • A
    $55^\circ $
  • B
    $25^\circ$
  • C
    $65^\circ$
  • $35^\circ$
Answer
Correct option: D.
$35^\circ$
Let the smaller angle be $x.$
Then,The larger angle $= (x + 20^\circ )$
As, the sum of the two complementary angles is always $90^\circ .$
$\Rightarrow x + (x + 20^\circ ) = 90^\circ $
$\Rightarrow 2x + 20^\circ = 90^\circ $
$\Rightarrow 2x = 90^\circ - 20^\circ $
$\Rightarrow 2x = 70^\circ $
$\Rightarrow\text{x}=\frac{70^\circ}{2} ($By transposing $2$ to $R.H.S.)$
$\therefore\text{x}=35^\circ$
So, the smaller angle is $35^\circ .$
Hence, the correct alternative is option $(d).$
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MCQ 681 Mark
The equation having $-3$ as a solution is:
  • A
    $x + 3 = 1$
  • B
    $8 + 2x = 3$
  • $10 + 3x = 1$
  • D
    $2x + 1 = 3$
Answer
Correct option: C.
$10 + 3x = 1$
 
Let us solve the equation:
$a.$ Given equation is $x + 3 = 1$
$\Rightarrow x = 1 - 3$
$\Rightarrow x = -2$
$b.$ Given equation is $8 + 2x = 3$
$\Rightarrow 2x = 3 - 8$
$\Rightarrow 2x = -5$
$\Rightarrow\text{x}=-\frac{5}{2}$
$c.$ Given equation is $10 + 3x = 1$
$\Rightarrow 3x = 1 - 10$
$\Rightarrow 3x = -9$
$\Rightarrow x = -3$
Now, we don't have to solve next equation as we get the answer.
 
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MCQ 691 Mark
If $a$ and $b$ are positive integers, then the solution of the equation $ax = b$ will always be $a.$
  • Positive number.
  • B
    Negative number.
  • C
    $1$
  • D
    $0$
Answer
Correct option: A.
Positive number.

Given equation is $ax = b$
On dividing the equation by $a,$ we get
$\text{x}=\frac{\text{b}}{\text{a}}$
Now, if $a$ and $b$ are positive integers, then the solution of the equation is also positive number as division of two positive integers is also a positive number.

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MCQ 701 Mark
If $x$ is an even number then the consecutive even number is:
  • A
    $x + 1$
  • $x + 2$
  • C
    $2x$
  • D
    $x - 2$
Answer
Correct option: B.
$x + 2$

Any even number is of the form $x = 2n$ where $n$ is an integer So then consecutive even number will be $2n + 2$ i.e $x + 2$

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MCQ 711 Mark
$\frac23$ of a number is less than the original number by $20.$ The number is:
  • A
    $30$
  • B
    $40$
  • C
    $50$
  • $60$
Answer
Correct option: D.
$60$

Let the number be $x.$
As, $23$ of the number is less than the original number by $20.$
$\Rightarrow\text{x}-\frac23\text{x}=20$
$\Rightarrow\frac{\text{x}}{1}-\frac{\text{2x}}{3}=20$
$\Rightarrow\frac{\text{3x}}{\text{3}}-\frac{\text{2x}}{3}=20$
$\Rightarrow\frac{\text{3x}-\text{2x}}{3}=20$
$\Rightarrow\frac{\text{x}}{3}=20$
$\Rightarrow\text{x}=20\times3 ($By transposing $3$ to $R.H.S.)$
 $\therefore\text{x}=60$
So, the number is $60.$
Hence, the correct alternative is option $(d).$

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MCQ 721 Mark
If $2\text{x}+\frac{1}{3\text{x}}=5$ then the value of $\frac{5\text{x}}{6\text{x}^2 + 20\text{x} + 1}$ is:
  • A
    $\frac{3}{7}$
  • B
    $\frac{2}{7}$
  • $\frac{1}{7}$
  • D
    $\frac{4}{7}$
Answer
Correct option: C.
$\frac{1}{7}$

$2\text{x}+\frac{1}{3\text{x}}=15$ Multiply both side by $3x$ Then So,
$\frac{5\text{x}}{6\text{x}^2+20\text{x}+1}=\frac{5\text{x}}{\text{6x}^2-15\text{x}+1+\text{35x}}=\frac{5\text{x}}{0+\text{35x}}\Rightarrow\frac{5\text{x}}{35\text{x}}=\frac{1}{7}$

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MCQ 731 Mark
Mark against the correct answer in the following:
Thrice a number when increased by $6$ gives $24.$ The number is:
  • $6$
  • B
    $7$
  • C
    $8$
  • D
    $11$
Answer
Correct option: A.
$6$

Let number $= x$ then
$3x + 6 = 24$
$\Rightarrow 3x = 24 - 6 = 18$
$\Rightarrow x = 6$
Number $= 6$

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MCQ 741 Mark
A number is as much greater than $31$ as it is less than $81.$ The number is:
  • A
    $46$
  • $56$
  • C
    $66$
  • D
    $76$
Answer
Correct option: B.
$56$
Let the number be $x.$
As, the number is as much greater than $31$ as it is less than $81.$
$⇒ x - 31 = 81 - x$
$⇒ x + x = 81 + 31 ($By transposing $-x$ to $L.H.S.$ and $-31$ to $R.H.S.)$
$⇒ 2x = 112$
$\therefore\text{x}=\frac{112}{2} ($By transposing $2$ to $R.H.S.)$
$\therefore\text{x}=56$
So, the number is $56.$
Hence, the correct alternative is option $(b).$
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MCQ 751 Mark
If $7x + 4 = 25,$ then $x$ is equal to:
  • A
    $\frac{29}{7}$
  • B
    $\frac{100}{7}$
  • C
    $2$
  • $3$
Answer
Correct option: D.
$3$

 Given equation is $7x + 4 = 25$
$⇒ 7x = 25 - 4 [$transposing $4$ to $RHS]$
$⇒ 7x = 21$
On dividing the above equation by $7,$ we get
$x = 3$
Hence, the solution of the given equation is $3.$

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MCQ 761 Mark
Mohan is $3$ years older than Sohan. The sum of their ages is $43$, then the age of Sohan is:
  • A
    $23$
  • $20$
  • C
    $18$
  • D
    $15$
Answer
Correct option: B.
$20$

 Let the age of Sohan $= x$
Now, age of Mohan $= x + 3$
Given, sum of their ages $=$
$\Rightarrow x + x + 3 = 43$
$\Rightarrow 2x + 3 = 43$
$\Rightarrow 2x = 43 - 3$
$\Rightarrow 2x = 40$
$\Rightarrow\text{x} = \frac{40}{2}$
$\Rightarrow x = 20$
So, age of Sohan is $20$ years

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MCQ 771 Mark
If  $f(x) = 3x - 4,$ then $f^{-1} =$
  • $\frac{\text{y +4}}{3}$
  • B
    $\frac{\text{y - 4}}{3}$
  • C
    $\frac{\text{y - 3}}{4}$
  • D
    $\frac{\text{y + 3}}{4}$
Answer
Correct option: A.
$\frac{\text{y +4}}{3}$
Solution: (A)  $\frac{\text{y +4}}{3}$
$f(x) = 3x - 4$ (Given) Say, $y = 3x - 4 ⇒ 3x = y + 4$​
$\Rightarrow\text{x}=\frac{\text{(y+4)}}{3}$
$ ∴\text{f}^1\text{(x)}=\text{x}=\frac{\text{y+4}}{3}$
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MCQ 781 Mark
The largest number of the three consecutive number is $x + 1$ then the smallest number is:
  • A
    $x + 2$
  • B
    $x + 1$
  • C
    $x$
  • $x - 1$
Answer
Correct option: D.
$x - 1$
 Largest of consecutive numbers is $(x + 1)$
We know that consecutive numbers differ by $1$
So consecutive number before $(x + 1)$ is $(x + 1) - 1$ i.e $x$
So the $1st$ number of three consecutive numbers will be $(x - 1)$
We know that $(x - 1) < x < (x + 1)$
So smallest of all consecutive numbers is $x - 1$
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MCQ 801 Mark
If $a$ and $b$ are positive integers, then the solution of the equation $ax = b$ is a:
  • positive number
  • B
    negative number
  • C
    $1$
  • D
    $0$
Answer
Correct option: A.
positive number

Given, $a$ and $b$ are positive integers
Again, $ax = b$
$ \Rightarrow \text{x} = \frac{\text{b}}{\text{a}}$
Since $a$ and $b$ are positive integers, So $ \frac{\text{b}}{\text{a}}$ is also a positive number.

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MCQ 811 Mark
If $\frac{\text{x}}{2}=3,$ then the value of $3x + 2$ is:
  • $20$
  • B
    $11$
  • C
    $\frac{13}{2}$
  • D
    $8$
Answer
Correct option: A.
$20$

Given, $\frac{\text{x}}{2}=3$
On muliplying both sides by 2, we get $\frac{\text{x}}{2}\times2=3\times2$
$\Rightarrow\text{x}=3\times2=6$
Put $x = 6$ in the equation $3x + 2,$ we get
$3(6) + 2 = 18 + 2 = 20$

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MCQ 821 Mark
The value of $y$ for which the expressions $(y - 15)$ and $(2y + 1)$ become equal is:
  • A
    $0$
  • B
    $16$
  • C
    $8$
  • $-16$
Answer
Correct option: D.
$-16$
It is given that both the expressions are equal. So the equation is:
$\Rightarrow y - 15 = 2y + 1$
$\Rightarrow y - 2y = 1 + 15 [$transposing $2y$ to $LHS$ and $(-15)$ to $RHS]$
$-y = 16$
Multiplying both sides by $(-1),$ we get
$y = -16$
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MCQ 831 Mark
The solution of the equation $m - 1 = 2$ is:
  • A
    $1$
  • B
    $2$
  • $3$
  • D
    $6$
Answer
Correct option: C.
$3$

$m - 1 = 2$
$\Rightarrow m = 2 + 1 = 3.$

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MCQ 841 Mark
Write the following statement in the form of an equation Add $1$ to three times $n$ to get $7:$
  • $3n + 1 = 7$
  • B
    $3n - 1 = 7$
  • C
    $3n + 7 = 1$
  • D
    None of these
Answer
Correct option: A.
$3n + 1 = 7$
$3n + 1 = 7$
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MCQ 851 Mark
Mark against the correct answer in the following:
Two complementary angles differ by $14^\circ .$ The larger angle is:
  • A
    $50^\circ $
  • $52^\circ$
  • C
    $54^\circ$
  • D
    $56^\circ$
Answer
Correct option: B.
$52^\circ$

Let the two complementary angles be $x^\circ $ and $(90 - x)^\circ .$
According to the equation, we have:
$x - (90 - x) = 14$
$\Rightarrow 2x = 104$
$\Rightarrow x = 52$
$(90^\circ - x)^\circ = 90^\circ - 52^\circ = 38^\circ $
The larger angle is $52^\circ .$

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MCQ 861 Mark
If $k + 7 = 16,$ then the value of $8k - 72$ is:
  • $0$
  • B
    $1$
  • C
    $112$
  • D
    $56$
Answer
Correct option: A.
$0$
Given equation is $k + 7 = 6$
On transposing $7$ to $RHS,$ we get
$k = 16 - 7 = 9$
Put the value of k in the equation $(8k - 72),$ we get
$8(9) - 72 = 72 - 72 = 0$
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MCQ 871 Mark
If $\frac{\text{x}+2}{\text{x}-2}=\frac{2}{3},$ then $x =$
  • $-10$
  • B
    $10$
  • C
    $\frac43$
  • D
    $-\frac43$
Answer
Correct option: A.
$-10$

As, $\frac{\text{x}+2}{\text{x}-2}=\frac{2}{3}$
$\Rightarrow3(\text{x}+2)=2(\text{x}-2)$ (By cross multiplication)
$\Rightarrow\text{3x}+6=2\text{x}-4$
$\Rightarrow\text{3x}-\text{2x}=-6+4 ($By transposing $2x$ to $L.H.S.$ and $6$ to $R.H.S.)$
$\therefore\text{x}=-10$
Hence, the correct alternative is option $(a).$

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MCQ 881 Mark
The solution of the equation $10y - 20 = 30$ is:
  • A
    $1$
  • B
    $2$
  • C
    $3$
  • $5$
Answer
Correct option: D.
$5$

$10y - 20 = 30$
$\Rightarrow 10y = 30 + 20 = 50$
$\Rightarrow\text{y} = \frac{50}{10} = 5$

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MCQ 901 Mark
Mark against the correct answer in the following:
If $\frac{\text{x}-1}{\text{x}+1}=\frac{7}{9}$, then $x =?$
  • A
    $6$
  • B
    $7$
  • $8$
  • D
    $10$
Answer
Correct option: C.
$8$

$\frac{\text{x}-1}{\text{x}+1}=\frac{7}{9}$
$\Rightarrow9\text{x}-9=7\text{x}+7$
$\Rightarrow9\text{x}-7\text{x}=7+9$
$\Rightarrow2\text{x}=16$
$\Rightarrow\text{x}=\frac{16}{2}=8$

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MCQ 911 Mark
Which of the following is not allowed in a given equation?
  • A
    Adding the same number to both sides of the equation.
  • B
    Subtracting the same number from both sides of the equation.
  • C
    Multiplying both sides of the equation by the same non$-$zero number.
  • Dividing both sides of the equation by the same number.
Answer
Correct option: D.
Dividing both sides of the equation by the same number.
Dividing both sides of the equation by the same non$-$zero number is allowed in a given equation, division of any number by zero is not allowed as set division of number by zero is not defined.
Note: If we add same number to both sides of the equation while adding subtracting, then there will be no change in the given equation.
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MCQ 921 Mark
The solution of the equation $ax + b = 0$ is:
  • A
    $\frac{\text{a}}{\text{b}}$
  • B
    $-\text{b}$
  • $-\frac{\text{b}}{\text{a}}$
  • D
    $\frac{\text{b}}{\text{a}}$
Answer
Correct option: C.
$-\frac{\text{b}}{\text{a}}$

Given equation is $ax + b = 0$
$\Rightarrow\text{ax}=-\text{b}[$ transposing b to $RHS]$
$\Rightarrow\text{x}=-\frac{\text{b}}{\text{a}} [$on dividing both sides by $a]$

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MCQ 931 Mark
The solution of the equation $x + 3 = 0$ is:
  • A
    $3$
  • $-3$
  • C
    $0$
  • D
    $1$
Answer
Correct option: B.
$-3$

$ x + 3 = 0$
$\Rightarrow x = -3.$

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MCQ 941 Mark
Number of sides on either side of equation in simple equation is:
  • A
    Three
  • Two
  • C
    $0$
  • D
    None of these
Answer
Correct option: B.
Two
Example of simple equation: $2x + 5 = y + 3$ Clearly we see that it has $2$ sides, left hand side $(LHS)$ and right hand side $(RHS)$
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MCQ 951 Mark
If $\frac{\text{x}}{6}+\frac{\text{x}}{4}=\frac{\text{x}}{2}+\frac{3}{4},$ then $x =$
  • A
    $9$
  • B
    $-6$
  • $-9$
  • D
    $4$
Answer
Correct option: C.
$-9$

 As, $\frac{\text{x}}{6}+\frac{\text{x}}{4}=\frac{\text{x}}{2}+\frac34$
$\Rightarrow\frac{\text{x}}{6}+\frac{\text{x}}{4}-\frac{\text{x}}{2}=\frac{3}{4} ($By transposing $\frac{\text{x}}{2}$ to $L.H.S.)$
$\Rightarrow\frac{2\text{x}}{12}+\frac{3\text{x}}{12}-\frac{6\text{x}}{12}=\frac{3}{4}$
$\Rightarrow\frac{2\text{x}+3\text{x}-6\text{x}}{12}=\frac34$
$\Rightarrow\frac{-\text{x}}{12}=\frac34$
$\Rightarrow-\text{x}\times4=3\times12$ (By cross multiplication)
$\Rightarrow-4\text{x}=36$
$\Rightarrow\text{x}=\frac{36}{-4}$
$\therefore\text{x}=-9$
Hence, the correct alternative is option $(c).$

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MCQ 961 Mark
Twelve years hence a man will be four times ashe was $12$ years ago, then his present age is:
  • A
    $25$ years
  • $20$ years
  • C
    $28 $ years
  • D
    $30$ years
Answer
Correct option: B.
$20$ years
 Let his present age be $x$
$12$ years ago his age was $x - 12$
$12$ years later his age will be $x + 12$
As per problem the followinge quation can be formed
$x + 12 = 4 (x - 12)$
$\Rightarrow x + 12 = 4x - 48$
$\Rightarrow x - 4x = -12 - 48$
$\Rightarrow -3x = -60$
$\Rightarrow x = 20$
His present age is $20$ years.
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MCQ 971 Mark
$3 (x - 1) = 3 (x) -3$ Classify this equation as a conditional equation:
  • An identity
  • B
    A contradiction
  • C
    Association
  • D
    None of the above.
Answer
Correct option: A.
An identity
$LHS = 3 (x - 1) = 3x -3$ which is equal to $RHS.$
Therefore, it is an identity.
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MCQ 981 Mark
A line has length of intersect $2$ and $3$ on $x-$axis and $y-$axis respectively, then the possible equation(s) of the line is/ are:
  • $\pm3\text{x}\pm2\text{y} = 6$
  • B
    $\pm2\text{x} ± 3\text{y} = 6$
  • C
    $3\text{x} + 2\text{y} = 6$
  • D
    $3\text{x} + 2\text{y} = -6$
Answer
Correct option: A.
$\pm3\text{x}\pm2\text{y} = 6$

Consider the given intersects $2$ and $3$ on $x-$axis $x−$axis and $y-$axis $y−$axis respectively.
$\text{a}=\pm2,\text{b}=\pm3$
We know that the equation of the line $\frac{\text{x}}{\text{a}}+\frac{\text{y}}{\text{b}}=1$
So, $\frac{\text{x}}{\pm2}+\frac{\text{y}}{\pm3}-1$
$\pm3{\text{x}}\pm2{\text{y}}=6$
Hence, this is the answer.

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MCQ 991 Mark
The solution of the equation $p + 4 = 4$ is:
  • $0$
  • B
    $4$
  • C
    $-4$
  • D
    $8$
Answer
Correct option: A.
$0$

$p + 4 = 4$
$\Rightarrow P = 4 - 4 = 0.$

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MCQ 1001 Mark
The solution of the equation $\frac{\text{m}}{2} = {3}$ is:
  • A
    $2$
  • B
    $3$
  • C
    $12$
  • $6$
Answer
Correct option: D.
$6$
$\frac{\text{m}}{2} = {3}$
$\Rightarrow m = 3 \times 2 = 6.$
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