Answer: the trip (one-way) that Alan made on Saturday was 63 miles.
Step-by-step explanation:
Let x represent the distance of the trip that Alan made on Saturday.
Let t represent the time that it took Alan to make the trip on Saturday.
On Saturday, Alan traveled North along minor roads averaging 36 mph to visit a friend.
Distance = speed × time.
Therefore, distance travelled on Saturday would be
x = 36 × t = 36t
On Sunday, he traveled East along main roads averaging 60 mph to visit his mother. The trip to visit his mother was 24 miles longer and took 18 minutes(18/60 = 0.3 hours) less. This means that the distance travelled would be
x + 24 and the time spent would be t - 0.3 hours.
Distance travelled on Sunday would be
x + 24 = 60(t - 0.3)
x + 24 = 60t - 18 - - - - - - -- - - 1
Substituting x = 36t into equation 1, it becomes
36t + 24 = 60t - 18
60t - 36t = 24 + 18
24t = 42
t = 42/24 = 1.75
x = 36t = 36 × 1.75
x = 63 miles
