Question

$650,000 was stolen from 1st Trust American Bank during a heist. The bank robbers got away clean and sped away traveling at a constant rate of 70 miles per hour. What the robbers did not realize is that one of the bank bags had a GPS tracking device inside of it. Once the police locked on to the signal of the tracking device they took off after the robbers traveling at a constant rate of 90 miles per hour. If the robbers already had a 30 mile head start, how long will it take the police to pass them and force them off the road to be arrested?

Answer 1

The time taken before the police force the robbers off the road is 1.5 hours

Explanation:

Answer 2

The time taken before the police force the robbers off the road is 1.5 hours

Explanation:

The speed with which the robbers were travelling = 70 miles per hour

The speed with which the police went after the robbers = 90 miles per hour

The distance with which the robbers were in front of the police before the police came after them = miles

Let t represent the time in hours the police force the robbers off the road, we have;

30 + 70 × t = 90 × t

30 = 90 × t - 70 × t = (90 - 70) × t = 20 × t

30 = 20 × t

20 × t = 30

t = 30/20 = 1.5

t = 1.5 hours

The time taken before the police force the robbers off the road = t = 1.5 hours