Web's Pancake House earned interest in 240 days from an investment that paid 3.5%. Find the amount initially invested.

Question

It is for me to learn how to do this because I don't know how to do this.

Answer 1

Do we assume the interest is compounded annually?

Also, we have two unknowns here ... the principal

investment and the amount of interest earned.  I think

you left out a piece of information:

 

240 days = 240/365 years = 48/73 of a year

 

A = p(1+r/n)^nt

A = future amount = principal + interest = p+i

p = principal investment

r = interest rate = 0.035

n = # times compounded per year = 1

t = time in years = 48/73

 

p + I = p(1+.035/1)^1(48/73)

 

To actually find the principal amount of investment we need
to know how much interest was earned