Question

At noon, a cargo van crosses an intersection at 26 mph. At 12:30 pm a car crosses the same intersection traveling in the opposite direction at 1 the van and car are 51 miles apart. How fast is the car traveling?

Answer 1

Let speed of car be x mph
At 1pm, cargo is 26 mph * 1 hour = 26 miles away from intersection.
At 1pm, car is x mph*30 minutes = x/2 miles from intersection.

Since it is given they travel in opposite directions, and are 51 miles apart, we have
26+x/2=51
Solve for x
x/2=51-26=25 mph
x=25*2=50 mph.
Car was travelling at 50 mph