Questions · Page 4 of 5

M.C.Q. [1 Marks Each]

MCQ 1511 Mark
Mark $(\checkmark)$ tick against the correct answer in the following:
Which of the following numbers is in standard form?
  • A
    $21.56 × 10^5$
  • B
    $215.6 × 10^4$
  • $2.156 × 10^6$
  • D
    None of these.
Answer
Correct option: C.
$2.156 × 10^6$
The number which is in standard form is $2.156 \times 10^6$
View full question & answer
MCQ 1521 Mark
Expanded form of $(-ab)^4$ is:
  • $(-ab) \times (-ab) \times (-ab) \times (-ab)$
  • B
    $4 \times (-ab)$
  • C
    $(-ab) \times (-ab)$
  • D
    $(-ab) \times (-ab) \times (-ab)$
Answer
Correct option: A.
$(-ab) \times (-ab) \times (-ab) \times (-ab)$
$(-ab)^4 = (-ab) \times (-ab) \times (-ab) \times (-ab)$
View full question & answer
MCQ 1531 Mark
If $2^n = 1024,$ then $2^{(\frac{\text{n}}{2}+2)}=$
  • A
    $64$
  • $128$
  • C
    $256$
  • D
    $512$
Answer
Correct option: B.
$128$
As, $2^n = 1024$
$\Rightarrow 2^n = 2^{10}$
Comparing the exponent of both the sides, we get:
$n = 10$
Now,
$2^{\Big(\frac{\text{n}}{2}+2\Big)}$
$=2^{\Big(\frac{\text{10}}{2}+2\Big)}$
$=2^{(5+2)}$
$=2^7$
$=128$
Hence, the correct alternative is option $(b)$.
View full question & answer
MCQ 1541 Mark
Which of the following is not equal to $1$?
  • A
    $\frac{2^{3}\times3^{3}}{4\times18}$
  • B
    $\big[(-2)^{3}\times(-2)^{4}\big]\div(27)^{7}$
  • C
    $\frac{2^{0}\times5^{3}}{5\times25}$
  • $\frac{2^{4}}{(7^{0}+3^{0})}$
Answer
Correct option: D.
$\frac{2^{4}}{(7^{0}+3^{0})}$

Let option $(a)$ $\frac{2^{3}\times3^{3}}{4\times18}=\frac{2\times2\times2\times3\times3}{4\times18}$
$=\frac{4\times18}{4\times18}=1$
For option $(b)$, $[(-2)^{3}\times(-2)^{4}]\div(-2)^{7}=\frac{(-2)^{3}\times(-2)^{}4}{(-2)^{7}}$
$=\frac{(-2)^{3+4}}{(-2)^{7}}$ $\big[\because\text{a}^{\text{m}}\times\text{a}^{\text{n}}=\text{a}^{\text{m+n}}\big]$
$=\frac{(-2)^{7}}{(-2)^{7}}=1$ $\big[\because\frac{\text{a}^{\text{m}}}{\text{a}^{n}}=\text{a}^{\text{m-n}}\big]$
For option $(c)$, $=\frac{3^{0}\times5^{3}}{5\times25}=\frac{1\times5\times5\times5}{5\times25}$
$=\frac{5\times25}{5\times25}=1$ $\big[\because\text{a}^{0}=1\big]$
For option $(d)$, $\frac{2^{4}}{(7^{0}+3^{0})^{3}}=\frac{2^{4}}{(1+1)^{3}}$ $\big[\because\text{a}^{0}=1\big]$
$=\frac{2^{4}}{2^{3}}=2^{4-3}$ $\big[\because\frac{\text{a}^{m}}{\text{a}^{\text{n}}}=\text{a}^{\text{m-n}},\text{m>n}\big]$
$=-2^{1}=2$
Hence, option $(d)$ is not equal to $1$.

View full question & answer
MCQ 1551 Mark
If $4^{2\text{x}}=\frac{1}{32},$ then the value of x is:
  • A
    $\frac{5}{4}$
  • $-\frac{5}{4}$
  • C
    $\frac{3}{4}$
  • D
    $-\frac{5}{2}$
Answer
Correct option: B.
$-\frac{5}{4}$

$4^{2\text{x}}=\frac{1}{32}$
$\Rightarrow(2^2)^{2\text{x}}=\frac{1}{2^5}$
$\Rightarrow2^{4\text{x}}2^{-5}$
$\Rightarrow4\text{x}=-5$
$\text{x}=\frac{-5}{4}$

View full question & answer
MCQ 1561 Mark
Mark $(\checkmark)$ tick against the correct answer in the following:
$\Big(\frac{5}{6}\Big)^0=?$
  • A
    $\frac{6}{5}$
  • B
    $0$
  • $1$
  • D
    None of these.
Answer
Correct option: C.
$1$

$\because\Big(\frac{5}{6}\Big)^0=1$ $\bigg\{\because\Big(\frac{\text{a}}{\text{b}}\Big)^0=1\bigg\}$

View full question & answer
MCQ 1571 Mark
In standard form $72$ crore is written as:
  • A
    $72 × 10^7$
  • B
    $72 × 10^8$
  • $7.2 × 10^8$
  • D
    $7.2 × 10^7$
Answer
Correct option: C.
$7.2 × 10^8$
We know that, A number in standard form is written as $a \times 10^k,$ where a is the terminating decimal such that $1 ≤ a ≤ 10$ and k is any integer.
So, $72$ crore
$= 720000000$
$=7X0^8$
Note Here, power of $10$ (i.e. k) is a positive integer equal to the number of places the decimal point has been shifted.
View full question & answer
MCQ 1581 Mark
Which power of $8$ is equal to $2^6?$
  • A
    $3$
  • $2$
  • C
    $1$
  • D
    $4$
Answer
Correct option: B.
$2$
Let power of $8$ be $x$.
According to the question,
$8^{\text{x}=2^{6}}$
$\Rightarrow(2)^{3\text{x}}=2^{6}$ $\big[\because8=2\times2\times2=2^{3}\big]$
$\Rightarrow2^{3\text{x}}=2^{6}$ $\big[\because(\text{a}^{\text{m}})^{\text{n}}=\text{a}^{\text{m}\times\text{n}}\big]$
Since, base equal, then by eqyating their exponents, we get
$3\text{x}=6$
$\Rightarrow\frac{3\text{x}}{3}=\frac{6}{3}$ [dividing both sides by $3$]
$\Rightarrow \text{x}=2$
Hence, the power of $8$ is $2,$ which is equal to $2^6$
View full question & answer
MCQ 1591 Mark
$10^6$ is expanded by writing - number of zeros after $1 -$
  • A
    $0$
  • $6$
  • C
    $10$
  • D
    None of these
Answer
Correct option: B.
$6$
$10^6= 10000006$ zeroes are present after $1$ in $10^6$
View full question & answer
MCQ 1601 Mark
Fourth power of $(-2)$ is:
  • A
    $-16$
  • B
    $-8$
  • C
    $+8$
  • $+16$
Answer
Correct option: D.
$+16$
$(-2)^4 = -2 \times -2 \times -2 \times -2 = 16$
View full question & answer
MCQ 1611 Mark
Standard form of $900000000000$ is:
  • $9 × 10^{11}$
  • B
    $9×10^8$
  • C
    $9×10^3$
  • D
    none
Answer
Correct option: A.
$9 × 10^{11}$
Standard form of $900000000000 = 9 \times 10^{11}$
View full question & answer
MCQ 1621 Mark
What should be multiplied to $6^{-2}$so that the product may be equal to $216?$
  • A
    $6^4$
  • $6^5$
  • C
    $6^3$
  • D
    $6$
Answer
Correct option: B.
$6^5$
Since,
Let $6^m$should be multiplied to $6^{-2}$
$A.T.Q.$
$6^{-2}× 6^m = 216$
$\Rightarrow 6^{-2+m} = 6^3$
Comparing th exponent of both the sides, we get
$-2 + m = 3$
$\Rightarrow m = 3 + 2$
$\therefore$ $m = 5$
So, $6^5$ should be multiplied.
Hence, the correct alternative is option $(b)$.
View full question & answer
MCQ 1631 Mark
The value of $a^4 - b^4$ is:
  • A
    $(a^2 - b^2)(a + b)(a - b)$
  • B
    $(a^2 - b^2)(a - b)(a - b)$
  • $(a^2 + b^2)(a + b)(a - b)$
  • D
    $(a^2 + b^2)(a + b)^2$
Answer
Correct option: C.
$(a^2 + b^2)(a + b)(a - b)$
$a4 - b4$
$= (a^2)^2 - (b^2)^2$ = $(a^2 + b^2)(a^2 - b^2)$​​​​​​​
$= (a^2 + b^2)(a + b)(a - b)$
View full question & answer
MCQ 1641 Mark
If $abc = 0$, then find the value of $\Big\{(\text{x}^{\text{a}})^{\text{b}}\Big\}^{\text{c}}$
  • $1$
  • B
    $a$
  • C
    $b$
  • D
    $c$
Answer
Correct option: A.
$1$
Since,
$\Big\{(\text{x}^{\text{a}})^{\text{b}}\Big\}^{\text{c}}$
$=(\text{x}^{\text{a}})^{\text{bc}}$ $[\text{As, }(\text{x}^{\text{m}})^{\text{n}}=\text{x}^{\text{mn}}]$
$=\text{x}^{\text{abc}}$ $[\text{As, }(\text{x}^{\text{m}})^{\text{n}}=\text{x}^{\text{mn}}]$
$=\text{x}^{0}$ $[\text{As, abc}=0]$
$=1$ $[\text{As, }\text{x}^{0}=1]$
Hence, the correct alternative is option $(a)$.
View full question & answer
MCQ 1651 Mark
The value of $(256)^\frac{5}{4}$ is:
  • A
    $512$
  • B
    $984$
  • $1024$
  • D
    $1032$
Answer
Correct option: C.
$1024$
$(256)^\frac{5}{4}=(4^4)^\frac{5}{4}$
$=4\Big(4\times\frac{5}{4}\Big)$
$=4^5=1024$
View full question & answer
MCQ 1661 Mark
Which expression is equivalent to $(9^{-2})$
  • A
    $-81$
  • $\frac{1}{81}$
  • C
    $81$
  • D
    $\text{None of these}$
Answer
Correct option: B.
$\frac{1}{81}$
Now, $9^{-2}=\frac{1}{9^2}=\frac{1}{81}$
View full question & answer
MCQ 1671 Mark
$2^{74} - 2^{73} - 2^{72}$ is same as:
  • $2^{72}$
  • B
    $2^{71}$
  • C
    $2^{70}$
  • D
    None of these
Answer
Correct option: A.
$2^{72}$
$2^{74} - 2^{73} - 2^{72}$
$= 2^{72} (2^2 - 2 - 1)$
$= 2^{72} × 1 = 2^{72}$
View full question & answer
MCQ 1681 Mark
In the $5^{th}$ term of $(x + y)^n,$ the exponent of $y$ is $4,$ then the exponent of $y$ in the $8^{th}$ term is:
  • A
    $1$
  • $7$
  • C
    $5$
  • D
    $9$
Answer
Correct option: B.
$7$
Given, $(x + y)^n$General term $\text{T}_{\text{r}+1}={^{\text{n}}}\text{C}_\text{r}\text{x}^{\text{n}-\text{r}}\text{y}^\text{r}\text{T}_{\text{r}+1}={^\text{n}}\text{C}_\text{r}(\text{x})^{\text{n}-\text{r}}\text{y}^\text{r}$
Given, in the $5^{th}$ term the exponent of $y$ is
$4\text{T}_5=\text{T}_{4+1}={^\text{n}}{\text{C}}_4(\text{x})^{\text{n}-4}\text{y}^4\text{T}_8=\text{T}_{7+1}={^\text{n}}{\text{C}}_7(\text{x})^{\text{n}-7}\text{y}^7$
Hence exponent of $y$ in the $8^{th}$ term is $7$
View full question & answer
MCQ 1691 Mark
Mark $(\checkmark)$ tick against the correct answer in the following:
$\Big(\frac{-1}{5}\Big)^3\div\Big(\frac{-1}{5}\Big)^8=?$
  • A
    $\Big(-\frac{1}{5}\Big)^5$
  • B
    $\Big(\frac{-1}{5}\Big)^{11}$
  • $(-5)^5$
  • D
    $\Big(\frac{1}{5}\Big)^5$
Answer
Correct option: C.
$(-5)^5$
$\because\Big(\frac{-1}{5}\Big)^3\div\Big(\frac{-1}{5}\Big)^8$
$=\Big(-\frac{1}{5}\Big)^{3-8}=\Big(-\frac{1}{5}\Big)^{-5}$
$=(-5)^5$
View full question & answer
MCQ 1701 Mark
$\Big\{(33)^2-(31)^2\Big\}^{\frac{5}{7}}$
  • A
    64
  • B
    16
  • 32
  • D
    4
Answer
Correct option: C.
32

Since,
$\Big\{(33)^2-(31)^2\Big\}^{\frac{5}{7}}$
$=\{1089-961\}^{\frac{5}{7}}$
$=\{128\}^{\frac{5}{7}}$
$=\{2^7\}^{\frac{5}{7}}$
$=2^{7\times\frac{5}{7}}$$[\text{As, }(\text{x}^{\text{m}})^{\text{n}}=\text{x}^{\text{mn}}]$
$=2^5$
$=32$
Hence, the correct alternative is option $(c)$.

View full question & answer
MCQ 1711 Mark
Mark $(\checkmark)$ tick against the correct answer in the following:
By what number should $(-8)^{-1}$ be multiplied to get $10^{-1}?$
  • A
    $\frac{4}{5}$
  • B
    $\frac{-5}{4}$
  • $\frac{-4}{5}$
  • D
    None of these.
Answer
Correct option: C.
$\frac{-4}{5}$
Required number $= 10^{-1} ÷ (-8)^{-1}$
$=\frac{1}{10}\div \Big(\frac{1}{-8}\Big)=\frac{1}{10}\times \frac{-8}{1}$
$=\frac{-4}{5}$
View full question & answer
MCQ 1721 Mark
100000000000 in standard form is
  • A
    $1 \times 10^{8}$
  • B
    $1 \times 10^{9}$
  • C
    $1 \times 10^{10}$
  • $1 \times 10^{11}$
Answer
Correct option: D.
$1 \times 10^{11}$
$1 \times 10^{11}$
View full question & answer
MCQ 1731 Mark
$1353000000$ in standard form is
  • $1.353 \times 10^{9}$
  • B
    $1.353 \times 10^{6}$
  • C
    $1.353 \times 10^{3}$
  • D
    $1.353 \times 10^{12}$
Answer
Correct option: A.
$1.353 \times 10^{9}$
$1.353 \times 10^{9}$
View full question & answer
MCQ 1741 Mark
$3430000$ in standard form is
  • $3.43 \times 10^{6}$
  • B
    $3.43 \times 10^{4}$
  • C
    $3.43 \times 10^{2}$
  • D
    $3.43 \times 10^{10}$
Answer
Correct option: A.
$3.43 \times 10^{6}$
$3.43 \times 10^{6}$
View full question & answer
MCQ 1751 Mark
$6000$ in standard form is
  • $6 \times 10^{3}$
  • B
    $6 \times 10^{6}$
  • C
    $6 \times 10^{4}$
  • D
    $6 \times 10^{5}$
Answer
Correct option: A.
$6 \times 10^{3}$
$6 \times 10^{3}$
View full question & answer
MCQ 1761 Mark
$333$ in standard form is
  • $3.33 \times 10^{2}$
  • B
    $3.33 \times 10^{3}$
  • C
    $3.33 \times 10^{1}$
  • D
    $3.33 \times 10^{4}$
Answer
Correct option: A.
$3.33 \times 10^{2}$
$3.33 \times 10^{2}$
View full question & answer
MCQ 1781 Mark
$a^{m} \div b^{m}=$
  • A
    $a^{m} b^{m}$
  • $\left(\frac{a}{b}\right)^{m}$
  • C
    $\frac{a}{b}$
  • D
    1
Answer
Correct option: B.
$\left(\frac{a}{b}\right)^{m}$
$\left(\frac{a}{b}\right)^{m}$
View full question & answer
MCQ 1791 Mark
$(-2 a)^{3}=$
  • A
    $2 a^{3}$
  • B
    $4 a^{3}$
  • C
    $8 a^{3}$
  • $-8 a^{3}$
Answer
Correct option: D.
$-8 a^{3}$
$(-2 a)^{3}=(-2 a) \times(-2 a) \times(-2 a)=-8 a^{3}$
View full question & answer
MCQ 1801 Mark
$82 ÷ 24 =$
  • A
    $1$
  • B
    $2$
  • C
    $3$
  • $4$
Answer
Correct option: D.
$4$
$8^{2}+2^{4}=\frac{(2 \times 2 \times 2)^{2}}{2^{4}}=\frac{\left(2^{3}\right)^{2}}{2^{4}}$
$=\frac{2^{3 \times 2}}{2^{4}}=\frac{2^{6}}{2^{4}}=2^{6-4}=2^{2}=4$
View full question & answer
MCQ 1811 Mark
$\left(\frac{a^{4}}{a^{2}} \times a^{3}=\right)$
  • A
    $a^{4}$
  • $a^{5}$
  • C
    $a^{6}$
  • D
    $a^{8}$
Answer
Correct option: B.
$a^{5}$
$\left(\frac{a^{4}}{a^{2}}\right) \times a^{3}=a^{4-2} \times a^{3}=a^{2} \times a^{3}$ $=a^{2+3}=a^{5}$
View full question & answer
MCQ 1821 Mark
$\frac{3^{8}}{3^{5} \times 3^{3}}=$
  • $1$
  • B
    $3$
  • C
    $5$
  • D
    $8$
Answer
Correct option: A.
$1$
$\frac{3^{8}}{3^{5} \times 3^{3}}=\frac{3^{8}}{3^{5+3}}=\frac{3^{8}}{3^{8}}=1$
View full question & answer
MCQ 1831 Mark
$\left(2^{2} \times 2\right)^{2}=$
  • A
    $2^{3}$
  • B
    $2^{4}$
  • C
    $2^{5}$
  • $2^{6}$
Answer
Correct option: D.
$2^{6}$
$\left(2^{2} \times 2\right)^{2}=\left(2^{2+1}\right)^{2}=\left(2^{3}\right)^{2}=2^{3 \times 2}=2^{6}$
View full question & answer
MCQ 1841 Mark
Which of the following is true?
  • $2^{0}=(100)^{0}$
  • B
    $10^{2} \times 10^{8}=10^{16}$
  • C
    $2^{2} \times 3^{3}=65$
  • D
    $2^{3}>3^{2}$
Answer
Correct option: A.
$2^{0}=(100)^{0}$
$2^{0}=(100)^{0}=1$
View full question & answer
MCQ 1861 Mark
$\left(2^{0}+3^{0}\right) \times 4^{0}=$
  • A
    $1$
  • $2$
  • C
    $3$
  • D
    $4$
Answer
Correct option: B.
$2$
$\left(2^{0}+3^{0}\right) \times 4^{0}=(1+1) \times 1=2$
View full question & answer
MCQ 1871 Mark
$3^{0} \times 4^{0} \times 5^{0}=$
  • $1$
  • B
    $3$
  • C
    $4$
  • D
    $5$
Answer
Correct option: A.
$1$
$3^{0} \times 4^{0} \times 5^{0}=1 \times 1 \times 1=1$
View full question & answer
MCQ 1891 Mark
If a is any non-zero integer, then $\mathrm{a}^{0}=$
  • A
    $a$
  • B
    $0$
  • $1$
  • D
    none of these
Answer
Correct option: C.
$1$
$1$
View full question & answer
MCQ 1901 Mark
$\left(\mathrm{a}^{\mathrm{m}}\right)^{\mathrm{n}}=$
  • A
    $\mathrm{a}^{\mathrm{m}+\mathrm{n}}$
  • B
    $\mathrm{a}^{\mathrm{m}-\mathrm{n}}$
  • $\mathrm{a}^{\mathrm{mn}}$
  • D
    $\mathrm{a}^{\mathrm{m} / \mathrm{n}}$
Answer
Correct option: C.
$\mathrm{a}^{\mathrm{mn}}$
$\mathrm{a}^{\mathrm{mn}}$
View full question & answer
MCQ 1911 Mark
$\left(5^{2}\right)^{10}=$
  • A
    $5^{2}$
  • $5^{20}$
  • C
    $5^{10}$
  • D
    $5^{5}$
Answer
Correct option: B.
$5^{20}$
$\left(5^{2}\right)^{10}=5^{2 \times 10}=5^{20}$
View full question & answer
MCQ 1931 Mark
$a m \div a n=$
  • A
    $a^{m+n}$
  • $a^{m-n}$
  • C
    $\mathrm{a}^{\mathrm{mn}}$
  • D
    $\mathrm{a}^{\mathrm{m} / \mathrm{n}}$
Answer
Correct option: B.
$a^{m-n}$
$a^{m-n}$
View full question & answer
MCQ 1941 Mark
$a^{m} \times a^{n}=$
  • $a^{m+n}$
  • B
    $a^{m-n}$
  • C
    $a^{m n}$
  • D
    $a^{m / n}$
Answer
Correct option: A.
$a^{m+n}$
$a^{m+n}$
View full question & answer
MCQ 1951 Mark
$(-5)^{4}=$
  • A
    $125$
  • $625$
  • C
    $375$
  • D
    $125$
Answer
Correct option: B.
$625$
$(-5)^{4}=(-5) \times(-5) \times(-5) \times(-5)=625$
View full question & answer
MCQ 1961 Mark
$b \times b \times b \times b \times b=$
  • $b^{5}$
  • B
    $b^{4}$
  • C
    $b^{6}$
  • D
    $b^{3}$
Answer
Correct option: A.
$b^{5}$
$b^{5}$
View full question & answer
MCQ 1971 Mark
$10^{6} \div 10^{5}=$
  • $10^{1}$
  • B
    $10^{5}$
  • C
    $10^{6}$
  • D
    $10^{11}$
Answer
Correct option: A.
$10^{1}$
$10^{6} \div 10^{5}=10^{6-5}=10^{1}$
View full question & answer
MCQ 1981 Mark
$2^{7} \div 2^{3}=$
  • $2^{4}$
  • B
    $2^{10}$
  • C
    2
  • D
    $\frac{1}{2}$
Answer
Correct option: A.
$2^{4}$
$2^{7} \div 2^{3}=2^{7-3}=2^{4}$
View full question & answer
MCQ 1991 Mark
If $(-3)^{4} \times(-3)^{6}=(-3)^{?},$ then $?=$
  • A
    $4$
  • $10$
  • C
    $6$
  • D
    $12$
Answer
Correct option: B.
$10$
$(-3)^{4} \times(-3)^{6}=(-3)^{4+6}=(-3)^{10}$
View full question & answer
MCQ 2001 Mark
If $2^{3} \times 2^{4}=2^{7}$, then $?=$
  • A
    $3$
  • B
    $4$
  • C
    $1$
  • $7$
Answer
Correct option: D.
$7$
$2^{3} \times 2^{4}=2^{3+4}=2^{7}$
View full question & answer
M.C.Q. [1 Marks Each] - Page 4 - Maths STD 7 Questions - Vidyadip