Questions · Page 2 of 2

1 Marks Question

Question 511 Mark
In whole numbers, $x + 8 = 12 - 4$ has _______ solution.
Answer
Solve the given equation for $x,$
$x + 8 = 12 - 4$
$\Rightarrow x + 8 = 8$
$\Rightarrow x = 8 - 8 [$transosing $8$ to $RHS]$
$\Rightarrow x = 0$
Since, zero is in the range of whole numbers, hence the equation has one solution.
View full question & answer
Question 521 Mark
Sum of two numbers is $81.$ One is twice the other. The solution of the equation is ________.
Answer
Now, solve the equation for $x,$
$\Rightarrow\text{x}+2\text{x}=81$
$\Rightarrow3\text{x}=81$
$\Rightarrow\frac{3\text{x}}{3}=\frac{81}{3} [$dividing both sides by $3]$
$\text{x}=27$
Hence, the solution of the equation is $27.$
View full question & answer
Question 531 Mark
$4x - 5 = 7$ does not have an integer as its solution.
Answer
Given equation is $4x - 5 = 7$
$\Rightarrow 4x = 7 + 5 [$transposing $(-5)$ to $RHS]$
$\Rightarrow 4x = 12$
On dividing both sides by $4,$ we get $x = 3($integer$)$
View full question & answer
Question 541 Mark
The length of a rectangle is two times its breadth. Its perimeter is $60\ cm.$
If the breadth of rectangle is $x\ cm$, the length of the rectangle is _________.
Answer
It is given that the length of the rectangle is two times its breadth.
$\therefore$ Length $= 2x\ cm$
View full question & answer
Question 551 Mark
$x + 7 = 10$ has the solution ________.
Answer
Solve the given equation for $x,$
$x + 7 = 10$
$\Rightarrow x = 10 - 7 [$transposing $7$ to $RHS]$
$\Rightarrow x = 3$
View full question & answer
Question 561 Mark
The sum of two numbers is $60$ and their difference is $30.$ The solution of the equation is _______.
Answer
Let us solve the equation for $x,$
$2x = 30$ On dividing the above equation by $2,$
we get $\frac{2\text{x}}{2}=\frac{30}{2}$
$\Rightarrow\text{x}=15$
Hence, the solution of the equation is $15.$
View full question & answer
Question 571 Mark
The length of a rectangle is two times its breadth. Its perimeter is $60\ cm.$ The equation formed is _______.
Answer
As we are given that perimeter of rectangle is $60\ cm.$ So, the equation formed is $2(2x + x) = 60$
$\Rightarrow 2(3x) = 60$
$\Rightarrow 6x = 60$
View full question & answer
Question 581 Mark
In a Mathematics quiz, $30$ prizes consisting of $1st$ and $2nd$ prizes only are to be given. $1st$ and $2nd$ prizes are worth $Rs. 2000$ and $Rs. 1000,$ respectively. If the total prize money is $Rs. 52,000$ then show that: If $1st$ prizes are $x$ in number the number of $2nd$ prizes are _______.
Answer
$1st$ prizes are $x$ in number, the number of $2nd$ prizes are $(30-x),$ because total number of prizes are $30$
View full question & answer
Question 591 Mark
The sum of twice a number and $4$ is $18.$
Answer
Let the number be $x.$
Then, sum of twice of a number and $4$ gives result $18.$
Hence, $2x + 4 = 18$ is the equation.
View full question & answer
Question 601 Mark
$13$ subtracted from twice of a number gives $3.$
Answer
Let the number be $x.$
$13$ is subtracted from twice of a number i.e,
$2x - 13$ and it results $3.$
So, the equation formed is $2x -13 = 3$
View full question & answer
Question 611 Mark
In integers, $4x - 1 = 8$ has ________ solution.
Answer
Solve the equation for $x,$
$4x - 1 = 8$
$\Rightarrow 4x = 8 + 1 [$transposing $(-1)$ to $RHS]$
$\Rightarrow 4x = 9$
$\Rightarrow\frac{4\text{x}}{4}=\frac{9}{4} [$dividing both sides by $4]$
$\Rightarrow\text{x}=\frac{9}{4}$
Since, the solution of the equation is an integer,
hence the equation has no solution.
View full question & answer
1 Marks Question - Page 2 - MATHS STD 7 Questions - Vidyadip