6 years ago, Adriana won some money in the lottery and put it in a bank account that earns 10% interest compounded annually. If Adriana currently has 400.00 in the bank account, how much interest has she earned?

Solution

6 ye a rs a g o, A d r iana w o n so m e m o n ey in t h e l o tt ery an d p u t i t in a bank a cco u n t t ha t e a r n s 10% in t eres t co m p o u n d e d ann u a ll y . I f A d r iana c u rre n tl y ha s 400.00 in t h e bank a cco u n t, h o w m u c h in t eres t ha s s h e e a r n e d ?

Interest : 174.21

Solution steps

Translate the problem into an equation:

400 = 225.78957 \dots + I

Solve for

I, 400 = 225.78957 \dots + I : I = 174.21

Interest : 174.21