Find the amount to be paid at the end of 3 years in each case:

(a) Principal = Rs. 1,200 at 12% p.a.

(b) Principal = Rs. 7,500 at 5% p.a.

(a) According to the question,

Principal (P) = Rs 1200

Rate (R) = 12 % p.a.

Time (T) = 3 years

We know that,

Simple interest (S.I) =

Therefore,

S.I =

= 12 × 12 × 3

= 144 × 3

= Rs 432

Hence,

Amount = Principal + S.I

= 1200 + 432

= Rs 1632

(b) According to the question,

Principal (P) = Rs 7500

Rate (R) = 5 % p.a.

Time (T) = 3 years

We know that,

Simple interest (S.I) =

Therefore,

S.I =

= 75 × 5 × 3

= 75 × 15

= Rs 1125

Hence,

Amount = Principal + S.I

= 7500 + 1125

= Rs 8625