Question

Find the sum of money when

(ii) the final amount is Rs 11300 at 4% p.a. for 3 years 3 months.

Answer 1

Amount (A) = Rs 11300

Rate (R) = 4% p.a.

Time (T) = 3 years 3 months

= $3\frac{3}{12}$ years

= $3\frac{1}{4}$years

= 13 / 4 years

Let the principal be Rs x

Hence,

S.I. = (P × R × T) / 100

= Rs (x × 4 × 13) / (100 × 4)

We get,

= Rs 13x / 100

Then,

Amount = Principal + Simple Interest

= Rs x + Rs 13x / 100

= Rs (x + 13x) / 100

We get,

= Rs (100x + 13x) / 100

= Rs (113x / 100)

But, the amount given is Rs 11300

Hence,

113x / 100 = 11300

x = 11300 × 100 / 113

x = 100 × 100

We get,

x = 10000

Therefore, principal (P) = Rs 10000