120 000 dollars is the cost of her house. She paid a downpayment which is 20% of it. 120000 * .20 = 24000 dollars => 120 000 - 24 000 = 96 000 dollars. She paid it for installment for 20 years wth 6.5% interest. => 96000 * .065 = 6240 dollars interest per year => 6240 dollars * 20 years = 124 800 dollars => 96 000 + 124 800 = 220 800 dollars.
