an executive invest $25,000, some at 7% and the rest at 5% annual interest. if he receives an annual return of $1,490, how much is invested at each rate?

Question

an executive invest $25,000, some at 7% and the rest at 5% annual interest. if he receives an annual return of $1,490, how much is invested at each rate?

Answer 1

.07x + .05y = 1490

x + y = 25000

y = 25000 - x

substitute into top equation:

.07x + .05(25000 - x) = 1490

.07x + 1250 -.05x = 1490

.02x +1250=1490

.02x =240

x=12000

plug x into Y= 25000 - x

y = 25000 - 12000

y = 13000

.07(12000) + .05(13000) = $1490

.

Answer 2

a + b = 25000

0.07a + 0.05b = 1490

a = 25,000 - b (or, b = 25,000 - a)

0.07(25,000 - b) + 0.05b = 1490

1750 - 0.07b + 0.05b = 1490

-0.02b = -260

b = $13,000

a = 25,000 - 13,000

a = $12,000