2 years ago, Ian won some money in the lottery and put it in a bank account that earns 4% interest compounded annually. If Ian currently has 200.00 in the bank account, how much interest has he earned?

解答

2 ye a rs a g o, I an 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 4% in t eres t co m p o u n d e d ann u a ll y . I f I an c u rre n tl y ha s 200.00 in t h e bank a cco u n t, h o w m u c h in t eres t ha s h e e a r n e d ?

Interest : 15.09

求解步骤

Translate the problem into an equation:

200 = 184.91124 \dots + I

求解

I, 200 = 184.91124 \dots + I : I = 15.09

Interest : 15.09