word problem

Question

Lily invested a total of $51,000 in two accounts. One account pays 5.5% interest annually; the other pays 6.9% interest annually. At the end of the year, Lily earned a total interest of $2,847. How much money did Lily invest in each account?

Answer 1

If A is the amount invested in the first account, then 51000 - A was invested in the 2nd.

2847 = 0.055A + 0.069(51000 - A)

Solve for A and you can derive the other amount invested as well.