Question 44689
Use the formula for interest:  I = prt
I=interest
p=principle
r=rate or percent
t=time in years (annually)
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Plug-in the known values into the formula for interest and solve for the unknown variable:
I = prt
$165=(1500)(r)(1)
165=1500r
165/1500=4
.11=r or 11% is the rate.
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For the second part, plug-in the known values into the formula for interest and solve for the unknown variable:
I = prt
I=(2500)(.11)(1)
I=$275