Your friend's parents deposited $8000 in an account paying 6.6% interest compounded quarterly. what will the account balance be after 16 years?
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Formula= A=P(1+r/n)^nt  
n=interest compounded quarterly(4) t=time(16) P=starting amount(8000) r=percent interest (6.6%)
A=8000(1+.066/4)4*16 
Put in your calculator .066/4 then add 1 to answer 
A=8000 (1.0165)^4*16
Multiply 4 and 16
A=8000(1.0165)^64
Plug into your calculator 
And your Answer would be: The account balance would be $22,801.45 after 16 years.