Solve the problem.
-An airplane leaves Los Angeles for Denver at a speed of 420 mph. Thirty minutes later, a plane going from Denver to Los Angeles leaves Denver, which is 850 miles from Los Angeles, at a speed
Of 520 mph. When they meet, how far are they from Denver?
A) 61 mi
B) 354 mi
C) 123 mi
D) 307 mi

Question

Quizplus · Accepted Answer

The first plane travels for 0.5 hours before the second plane starts, covering 210 miles (420 mph * 0.5 hours). The distance between the planes when the second plane starts is 850 - 210 = 640 miles. The planes are moving towards each other at a combined speed of 940 mph (420 mph + 520 mph). The time taken to meet is 640 miles / 940 mph = 0.68 hours. The distance the second plane travels in this time is 0.68 hours * 520 mph = 354 miles. Thus, they are 354 miles from Denver when they meet.

Solve the Problem. -An Airplane Leaves Los Angeles for Denver at a Speed