Aidan has $65 in his bank account. His brother Michael also has a bank account. They want to calculate the amount of money in both accounts combined. What variable is needed to calculate their combined total?
A.
m, the amount of money in Michael's bank account
B.
d, the difference between the amounts in Aidan's and Michael's account
C.
l, the amount of money in Michael's account last month
D.
a, the amount of money in Aidan's bank account