Problema Solution
The amount of money invested at 5% simple interest was half the amount invested at 7% simple interest. If the total yearly interest earned was $380, how much money was invested at each rate?
Answer provided by our tutors
let 'x' represent the amount invested at 5%, then '2x' represents the amount invested at 7%
interest = principal * rate * time
we assume time to be equal to 1
380 = 0.05x + 0.07(2x)
solving for 'x' we have x=2000
2000*2 = 4000
$2,000 was invested at 5%, $4,000 was invested at 7%