Answer:
A. The interest at the end of the six months will be $13.8. B. Miguel must pay $413.8.
Explanation:
Step 1: First we must calculate the annual interest of 6.9% on the total debt ($400).
$400 * 6,9%/100% = $27,6
This amount would be the equivalent of one year's repayment of the debt.
Step 2: As only six months passed, the interest to be paid will be half of what is equivalent to the annual interest.
$27,6 / 2 = $13,8
This is the amount of interest to be paid during the six months.
Step 3: Finally, to calculate the final amount that Miguel will have to pay, we add the amount of the debt acquired with the interest produced during the six months.
$400 + $13,8 = $413,8
Have a nice day!