Question

SI for a certain sum of money is Rs.30 in 4 years and Rs. 60 in 6 years. Rate of

interest in both cases is 10 % p.a. Find the sum.​

Answer 1

$\large \bf{\blue{Answer:}}$

Sum for 4 years is ₹ 105 & sum for 6 years is ₹ 160.

$\large\bf{\blue{Step-by-step \: explanation:}}$

Simple Interest → SI

Rate of interest → R

No. of years → T

Principal Amount → P

Formula for SI = (P × R × T) ÷ 100

Solution:

Case 1:-

SI = ₹ 30, T = 4 years, R = 10%

SI = (P×R×T)÷100

30 = P × 10 × 4 ÷ 100

30 = P × 4 ÷10

P = 30 × 10 ÷ 4

P = ₹ 75

Sum for 4 years = ₹75 + ₹30 = ₹105

Case 2:-

SI = ₹ 60,  T = 6 years, R = 10 %

SI = PRT ÷ 100

60 = P × 10 × 6 ÷ 100

P = 60 ×100 ÷60

P = ₹ 100

Sum for 6 years = ₹100+ ₹60 = ₹160