Question 285014
Let the speed of the car be x feet/sec

Truck speed = 45 mph

The effective speed of the car is x-45 mph ( because they are in the same direction)

The car has to travel 15feet +30 feet to completely pass the truck = 45 feet

45 mph =66 ft/sec

Speed = distance / time


x-66 = 45 / 3

x-66=15

x=66+15

x= 81 ft/sec

=55 mph