Since you are trying to determine the exponent you need to work with logs
Number of periods = ln(FV/PV)/ln(1 + r)
r = 0.039/12 = 0.00325
Give it a try
Brenda D.
tutor
Is the above the correct formula for your class. I ask because in another question you had A=P(1+i)n. According to what you have listed as your rate 3.90%, your annual rate, that is compounded monthly which means 12 times per year 3.90/12*.01 would take a very long time; like 1371 months or 114 years. Are you using a Futrue Values table of some sort for your class.
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10/21/20
Brenda D.
tutor
A=P(1+i)n solving for n=A/P(1 + i)= 7700/(90*1.00325)= 85.278 or 85, if n in your formula is in years then you would still have to multiply by 12 to get the number of months.
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10/21/20
Sean M.
I do not know how to get the months10/20/20