Answer:
$50,460.87 of interest has been accrued.
Step-by-step explanation:
Richard deposits $193.67 every month into his mortgage.
Each year as 12 months. So after 30 years he will have deposited:
$193.67*12*30 = $69,721.2
At the end of 30 years, he has a balance of $120,182.07. What interest has accrued (been earned) over 30 years?
Interest is total subtracted by deposits. So
120,182.07 - 69,721.2 = $50,460.87
$50,460.87 of interest has been accrued.