Alanna can detail a car in 45 minutes. Robbie can detail a car in 30 minutes. If they work together, how many minutes does it take them to detail a car?
A.) 15 minutes
B.) 18 minutes
C.) 75 minutes
D.) 90 minutes
A.) 15 minutes
B.) 18 minutes
C.) 75 minutes
D.) 90 minutes