Question

Find the simple interest and the amount when:
$$Principal = Rs.9600, rate = 7 \dfrac{1}{2}\% \,p.a.$$ and $$time = 5 \,months.$$

Answer 1

Given:- $$P = Rs. 9600, R = 7 \dfrac{1}{2}\% \,p.a. = (15 / 2)$$ and $$time = 5 \,months = (5 / 12) \,years$$
If interest is calculated uniformly on the original principal throughout the loan period, it is called simple interest.
$$SI = (P \times R \times T) / 100$$
$$= (9600 \times (15 / 2) \times (5 / 12)) / 100$$
$$= 9600 \times (15 / 2) \times (5 / 12) \times (1 / 100)$$
$$ = (9600 \times 15 \times 5 \times 1) / (2 \times 12 \times 100)$$
$$ = (96 \times 15 \times 5 \times 1) / (2 \times 12)$$
$$ = (7200) / (24)$$
$$Rs. 300$$
$$Amount = (principal + SI)$$
$$= (9600 + 300)$$
$$= Rs. 9900$$