A sum was invested partly at 6% p.a. simple interest and partly at 9% p.a. simple interest. The amount invested at 9% is 2,500 more than the amount invested at 6%. After 3 years, the total simple interest from both parts is 2,070. Find the amount invested at each rate.
Show answer & explanation
Correct answer: A
Explanation
Given:
Amount at 6% = x
Amount at 9% = x + 2500
Time = 3 years
Total Simple Interest = 2070
According to the formula:
Simple Interest = (P × R × T) / 100
Interest at 6% = (x × 6 × 3)/100 = 18x/100
Interest at 9% = ((x + 2500) × 9 × 3)/100 = 27(x + 2500)/100
Total Interest:
18x/100 + 27(x + 2500)/100 = 2070
18x + 27x + 67500 = 207000
45x + 67500 = 207000
45x = 139500
x = 3100
Therefore,
Amount at 6% = 3100
Amount at 9% = 3100 + 2500 = 5600
At 6% = 3100 Rupees, At 9% = 5600 Rupees