What could you do to solve the problem below?
Residents of Landry Island must take two ferries to get to the mainland. If
the first ferry trip is 31 minutes and the second ferry trip is 21 minutes, how
long does it take to get to the mainland?
A. Divide 31 by 21
B. Add 21 to 31
C. Subtract 21 from 31
D. Multiply 31 by 21