Question

A woman has a total of $8,000 to invest. She invests part of the money in an account that pays 11 % per year

and the rest in an account that pays 12% per year. If the interest earned in the first year is $920, how much did
she invest in each account?

Answer 1

Explanation:

art I 5.00% per annum ------------- Amount invested =x

Part II 9.00% per annum ------------ Amount invested = y

8000

Interest----- 520.00

Part I 5.00% per annum ---x

Part II 9.00% per annum ---y

Total investment

x + 1 y= 8000 -------------1

Interest on both investments

5.00% x + 9.00% y= 520

Multiply by 100

5 x + 9 y= 52000.00 --------2

Multiply (1) by -5

we get

-5 x -5 y= -40000.00

Add this to (2)

0 x 4 y= 12000

divide by 4

y = 3000

Part I 5.00% $ 5000

Part II 9.00% $ 3000

CHECK

5000 --------- 5.00% ------- 250.00

3000 ------------- 9.00% ------- 270.00

Total -------------------- 520.00