How much interest has Leroy earned?

Question

anonymous · Answer

Leroy opened a savings account 25 years ago with a deposit of $3,080.43. The account has an interest rate of 3.7% compounded monthly. How much interest has Leroy earned?

anonymous · Answer

i used f=3080.43(1+0.03712)12⋅5

anonymous · Answer

still wrong

ganeshie8 · Answer

try this

3080.43(1+0.037/12)^(12*25) - 3080.43

ganeshie8 · Answer

http://www.wolframalpha.com/input/?i=3080.43%281%2B0.037%2F12%29%5E%2812*25%29+-+3080.43

anonymous · Answer

thanks that worked

ganeshie8 · Answer

your formula gives the "total accumulated amount"
subtracting the starting amount gives you the interest

anonymous · Answer

@ganeshie8 what about this Malcolm deposited $567.21 in a savings account that earns 2.6% simple interest. What is Malcolm’s account balance after eight years?

 $117.98
 $685.19
 $1,179.80
 $581.96<<<< i got this is it correct

ganeshie8 · Answer

looks you forgot to multiply interest by 8

ganeshie8 · Answer

account balance after 8 years = 567.21 + 567.21*0.026*8

anonymous · Answer

i did

anonymous · Answer

oh ok i see

anonymous · Answer

i got 11.69168

ganeshie8 · Answer

http://www.wolframalpha.com/input/?i=567.21+%2B+567.21*0.026*8

anonymous · Answer

so i got it right

anonymous · Answer

thats closest to the questions

ganeshie8 · Answer

yes