​ On certain amount simple interest is 16/25th part of the amount taken then the time and rate of interest is ……………….. (Numerically same) ​

Question

On certain amount simple interest is \(\frac{16}{25}\)th part of the amount taken then the time and rate of interest is ……………….. (Numerically same) 

A) 8 

B) 9 

C) 10 

D) 3

Answer 1

Correct option is (A) 8

Let the amount taken be Rs P.

\(\therefore\) S.I. = \(\frac{16}{25}\times\) P = \(\frac{16P}{25}\)

R = T

\(\therefore\) S.I. = \(\frac{PRT}{100}\)

\(\Rightarrow\) \(\frac{16P}{25}\) = \(\frac{P\times R\times R}{100}\)  \((\because\)  R = T)

\(\Rightarrow\) \(R^2=\) \(\frac{16P}{25}\times\frac{100}P\) \(=16\times4=64=8^2\)

\(\Rightarrow\) R = 8

\(\Rightarrow\) T = R = 8

Answer 2

Correct option is  A) 8