1 q.10. Madhulika deposited two parts of a sum of rs. 25,000 in different banks at the rates of 15% per annum and 18% per annum respectively. In one year she got rs. 4050 as the total interest. What was the amount deposited at the rate of 15% per annum ?
Answers
Answer:
Amount deposited at 15% interest = Rs.15,000
Amount deposited at 18% interest = Rs.10,000
Step-by-step explanation:
Let the amount deposited at 15% interest = x
Hence, the amount deposited at 18% interest = 25000 - x
(Given that total amount = Rs.25,000)
Interest earned on 15% deposit in one year
= (x * 15 * 1)/100
= 15x / 100
(We have used simple interest formula SI = (P*R*T)/100)
Similarly, interest earned on 18% deposit in one year
= [(25000 - x)*18*1]/100
= [18(25000 - x)] / 100
We are given that total interest earned in 1 year is Rs.4050
Thus,
15x/100 + [18(25000 - x)] / 100 = 4050
15x + 18(25000 - x) = 405000
15x + 450000 - 18x = 405000
-3x = 405000 - 450000
-3x = -45000
3x = 45000
x = 15000
Hence, amount deposited at 15% interest = Rs.15,000
Also, amount deposited at 18% interest = 25000 - x = Rs.10,000
Verify
Interest earned in 1 year on Rs.15,000 at 15% = 15000*15*1/100 = 2250
Interest earned in 1 year on Rs.10,000 at 18% = 10000*18*1/100 = 1800
Total interest earned = 2250 + 1800 = 4050 (as given)