Carmen has taken out a loan for $800 to buy a car. she plans to pay back the loan at a rate of $40 per month. ramona has borrowed $500 to buy a car, which she plans to pay back at a rate of $20 per month.

how long will it take carmen to pay back her loan?
a.
25 months
b.
20 months
c.
15 months
d.
10 months