Problema Solution
Sandy invested her savings of $4500 in two different accounts one year ago. One account had an interest rate of 5% per year and the other had a rate of 7% per year. The total return from the investment was $280. How much was invested at each rate?
Answer provided by our tutors
let x was the amount ivested at 5% interest.
Interest = x*0.05*1=0.05x
Amount invested at 7% = 4500-x
Interest = (4500-x)*0.07 = 315 -0.07x
Hence, 0.05x+315-0.07x = 280
-0.02x = 280-315 = -35
x = 35/0.02 = 1750
Hence, amount invested at 5% interest = $1750
Amount invested at 7% interest = $(4500-1750) = $2750 Ans.