Answer:
$8,000 was loaned at a 9% interest rate
Step-by-step explanation:
Ok, so we know the bank loaned part of the $17,500 at a 4% interest rate. Lets call this loan amount x. Then the rest of the 17,500 was loaned at a 9% interest rate. Whatever this amount was, we can define it as 17,500 - x. We also know that the total interest earned was $1,100. With this information, we can form the following equation:
.04(x) + .09(17500 - x) = 1100
Multiply the .09 times the inside of the parentheses:
.04x + 1575 - .09x = 1100
Simplify:
-.05x + 1575 = 1100
-.05x = -475
x = 9500
Since x is originally the amount loaned at the 4% interest rate, we know that $9,500 was loaned at a 4% interest rate.
To figure out the other amount loaned at 9%, simply subtract 9,500 from 17,500 -- this gets us 8,000. So $8,000 was loaned at a 9% interest rate.
