Question

A sum of money amounts to RS 51,920 in 2 years and to RS 59,840 in 4 years at a certain rate of simple interest. Find the sum and the rate.​

Answer 1

Answer:

Let the Principal be Rs. P,

According to question,

P+S.I for 2 years = Rs. 51920 ... (i)

P+S.I for 4 years = Rs. 59840 ... (ii)

Substracting eq. (i) from eq. (ii),

We get,

S.I for 2 years = Rs. 7920

S.I for 1 year = Rs. 7920/2

= Rs. 3960

S.I for 4 years = Rs. (3960*4)

= Rs. 15840

Principal = Amount for 4 years - S.I for 4 years

= Rs. (59840-15840)

= Rs. 44000

S.I = [P*R*T]/100

= 3960 = [44000*R*1]/100

= 396000 = 44000R

= 9% p.a = Rate

The Principal is Rs. 44000 and Rate is 9% per annum.

I hope this helps.