Question

The present worth of a bill due 7 months hence is ₹1200. If the bill were due at the end of 2\(\frac{1}{2}\)yr, Its present worth would be Z ₹1016. What is the rate per cent of the bill?

• A. 8%
• B. 10%
• C. 16%
• D. 18%

Answer 1

The Correct Option is B

Since,

S.I. \(=\frac{Principal\times Rate\times Time}{100}\)

Therefore, 1200 + 1200\(\times\)7\(\times\)\(\frac{r}{12\times100}=\) Amount (A)

1200 + 7r = A .........(i)

and 1016 + 1016\(\times\)5\(\times\)\(\frac{r}{2}\times\)100 = A

Therefore, 1016 + 25.4r = A ...(ii)
1016 + 25.4r = 1200 + 7r
So,
25.4r - 7r = 1200 - 1016
18.4r = 184

r \(=\frac{184}{18.4}\) 

= 10\(\%\) per annum.
So the correct option is (B)