Question

Didi invested a total of $16125 in two accounts paying 8.5% and 4% simple interest. If her total return at the end of 2 years was 1740 , how much did she invest in each account?

Answer 1

5000 ;

11125

Explanation:

Given :

Total principal = 16125

Rates = 8.5% and 4%

Period, t = 2 years

Total interest = 1740

Let :

Principal amount invested at 8.5% = x

Principal amount invested at 4% = 16125 - x

Interest formula :

Interest = principal * rate * time

Hence, mathematically ;

(x * 8.5% * 2) + [(16125 - x) * 4% * 2] = 1740

(0.17x + 1290 - 0.08x ) = 1740

0.09x + 1290 = 1740

0.09x = 1740 - 1290

0.09x = 450

x = 450 / 0.09

x = 5000

Amount invested at 4% :

16125 - 5000 = 11125