Answer:the distance between the two cities is 100 miles
Explanation:
Let x represent the distance between New York and Philadelphia.
Let t represent the time it takes to travel from New York to Philadelphia at 50 mph
Distance speed × time
time = distance/speed
To travel from New York to Philadelphia at 50 mph,
x = 50t
it takes 20 more minutes than to travel the same distance at 60 mph. Converting 20 minutes to hours, it becomes 20/60 = 1/3 hours. This means that
x = 60(t - 1/3) = 60t - 20
Since the distance is the same,
60t - 20 = 50t.
60t - 50t = 20
10t = 20
t = 20/10 = 2
Therefore
x = 50t = 50 × 2 = 100 miles