Ms. Wilson invested ​$25,000 in two​ accounts

Question

Ms. Wilson invested ​$25,000 in two​ accounts, one yielding 4​% interest and the other yielding 9%.

If she received a total of​ $1550 in interest at the end of the​ year, how much did she invest in each​ account?

Answer 1

.05(25000-x) + .09(x) = 1550 where x = investment in 9%

.04x = 1550 - 1250 = 300

x = 300/.04 = about $7,500 at 9%

$ 17,500 at 5%

alternative solution method:

1550/25000 = 6.2%

6.2-5= 1.2 9-6.2 = 2.8

2.8/1.2 = 7/3 = x/(25000-x)

3x = 175000-7x

10x = 175,000

x = $17,500 invested at 5%, $7,500 at 9%