On Saturdays, the #14 bus makes roundtrips between Susan's school and the mall, and the #11 bus makes roundtrips between the mall and the museum.
Next Saturday, Susan wants to take the bus from her school to the museum. A
#14 bus leaves Susan's school every 15 minutes, beginning at 7 A. M. It takes the
bus 30 minutes to travel between the school and the mall. A #11 bus leaves the
mall every 12 minutes, beginning at 7 A. M.
a. If Susan gets on the #14 at 9:30 A. M., how long will she have to wait at the
mall for a #11 bus? Explain your reasoning,