Tyrone almost forgot that he promised to pick up a prescription for his mother at the drug store across town. His mother is due home in 45 minutes. If Tyrone is able to make the 12.5 mile trip to the store and back again before his mother gets home, can he obey the posted speed limit of 35 mph?

Question

Tyrone almost forgot that he promised to pick up a prescription for his mother at the drug store across town.  His mother is due home in 45 minutes.  If Tyrone is able to make the 12.5 mile trip to the store and back again before his mother gets home, can he obey the posted speed limit of 35 mph?

anonymous · Answer

He has 45 minutes to travel 25 miles.
v=d/t
25mi/.75 hr < 35?
True, assuming he takes no time in the drug store

anonymous · Answer

Round trip : 2 * 12.5 = 25 mi
speed : distance/ hours
hour = 45 min / 60 = .75 hr
=> speed = 25/ .75 = 33.3 mph ( < 35 mph limitation)