If Jake receive $12,000 and he will have to pay $3,600 as an interest rate, then he will need to give $12,000 + $3,600 = $15,600 overall. But to find the interest rate we need to find out how many percent of $12,000 is $3,600:
12,000 * x% = 3,600
12,000 * x/100 = 3,600 / * 100 (both sides)
12,000 * x = 360,000 / ÷ 12,000 (both sides)
x = 30
Doublecheck:
12,000 * 30% =
= 12,000 * 30/100 =
= 12,000 * 3/10 =
= 36,000/10 =
= 3,600
So it's correct.
Answer: The interest rate is 30%.
