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

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

Answer 2

Answer:

principle=150

6 years amount is 210

4 years amount is 180

Step-by-step explanation:

6years=60

4years=30 . simple interest

6years-4years=60-30

2years=30

1years=15

SI = (PTR)/100

15=(PX1X10)/100

150=P

P=150

for 6year amount =150+60=210

for 4years amount =150+30=180