Square Root and Cube Root Questions Answers
-
8. \begin{aligned}
(\frac{\sqrt{625}}{11} \times \frac{14}{\sqrt{25}} \times \frac{11}{\sqrt{196}})
\end{aligned}
- 15
- 7
- 5
- 9
Answer And Explanation
Answer: Option C
Explanation:
\begin{aligned}
= (\frac{25}{11} \times \frac{14}{5} \times \frac{11}{14})
\end{aligned}
\begin{aligned}
= 5
\end{aligned} -
9. Find the value of x
\begin{aligned}
\frac{2707}{\sqrt{x}} = 27.07
\end{aligned}
- 1000
- 10000
- 10000000
- None of above
Answer And Explanation
Answer: Option B
Explanation:
\begin{aligned}
= \frac{2707}{27.07} = \sqrt{x}
\end{aligned}
\begin{aligned}
=> \frac{2707 \times 100}{2707} = \sqrt{x}
\end{aligned}
\begin{aligned}
=> 100 = \sqrt{x}
\end{aligned}
\begin{aligned}
=> x = 100^2 = 10000
\end{aligned}
-
10. What is the square root of 0.16
- 0.4
- 0.04
- 0.004
- 4
Answer And Explanation
Answer: Option A
Explanation:
as .4 * .4 = 0.16
-
11. The least perfect square, which is divisible by each of 21, 36 and 66 is
- 213414
- 213424
- 213434
- 213444
Answer And Explanation
Answer: Option D
Explanation:
L.C.M. of 21, 36, 66 = 2772
Now, 2772 = 2 x 2 x 3 x 3 x 7 x 11
To make it a perfect square, it must be multiplied by 7 x 11.
So, required number = 2 x 2 x 3 x 3 x 7 x 7 x 11 x 11 = 213444 -
12. Evaluate
\begin{aligned}
\sqrt{0.00059049}
\end{aligned}- 0.00243
- 0.0243
- 0.243
- 2.43
Answer And Explanation
Answer: Option B
Explanation:
Very obvious tip here is, after squre root the terms after decimal will be half (that is just a trick), works awesome at many questions like this.
-
13. if a = 0.1039, then the value of
\begin{aligned} \sqrt{4a^2 - 4a + 1} + 3a \end{aligned}- 12.039
- 1.2039
- 11.039
- 1.1039
Answer And Explanation
Answer: Option D
Explanation:
Tip: Please check the question carefully before answering. As 3a is not under the root we can convert it into a formula , lets evaluate now :
\begin{aligned}
= \sqrt{4a^2 - 4a + 1} + 3a \end{aligned}
\begin{aligned}
= \sqrt{(1)^2 + (2a)^2 - 2x1x2a} + 3a \end{aligned}
\begin{aligned}
= \sqrt{(1-2a)^2} + 3a \end{aligned}
\begin{aligned}
= (1-2a) + 3a \end{aligned}
\begin{aligned}
= (1-2a) + 3a \end{aligned}
\begin{aligned}
= 1 + a = 1 + 0.1039 = 1.1039 \end{aligned}
-
14. Find the value of X
\begin{aligned} \sqrt{81} + \sqrt{0.81} = 10.09 - X \end{aligned}- 0.019
- 0.19
- 0.9
- 0.109
Answer And Explanation
Answer: Option B
Explanation:
\begin{aligned}
=> \sqrt{81} + \sqrt{0.81} = 10.09 - X
\end{aligned}
\begin{aligned}
=> 9 + 0.9 = 10.09 - X
\end{aligned}
\begin{aligned}
=> X = 10.09 - 9.9 = 0.19
\end{aligned}