Three-fifth of the square of a certain number is 126.15. What is the numbers ?
A. 14.5
B. 75.69
C. 145
D. 210.25
Answer: Option A
Solution(By Examveda Team)
$$\eqalign{ & {\text{Let the number be }}x \cr & {\text{Then,}} \cr & \Leftrightarrow \frac{3}{5}{x^2} = 126.15 \cr & \Leftrightarrow {x^2} = \left( {126.15 \times \frac{5}{3}} \right) \cr & \Leftrightarrow {x^2} = 210.25 \cr & \Leftrightarrow x = \sqrt {210.25} \cr & \Leftrightarrow x = 14.5 \cr} $$Related Questions on Square Root and Cube Root
The least perfect square, which is divisible by each of 21, 36 and 66 is:
A. 213444
B. 214344
C. 214434
D. 231444
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