How long does it take the second car to overtake the first?

Question

Two cars leave Erie for Washington. The first car to leave travels at an average speed of 63 kilometers per hour. The second car, which leaves 2 hours later, travels at an average speed of 69 kilometers per hour. How long does it take the second car to overtake the first?

Answer 1

d= rt = 63t = 69(t-2)= 69t - 138

distance = rate of speed times time = 63 kph times t hours = 69 kph times t-2 hours

6t = 138

t = 23 hours

t-2 = 21 hours for 2nd car to overtake the 1st

63(23) = 69(23-2) = 69(21)

distance = 1,449 km

1st speed = 63 kph

2nd speed = 69 kph

in 10 hours, 1st went 630 km

in 20 hours 1st went 1260

in 23 hours 1st went 1449

in 8 hours 2nd went 69(8) = 552 km

in 18 hours 2nd went 69(18) = 1242 km

in 21 hours 2nd went 69(21) = 1449 km

ignoring pitstops, traffic, toll roads, red lights, sleep, police, and for EV's recharging time

Erie to Seattle = about 2507 miles= about 4036.1 km

Erie to Washington DC is less than 300 miles

Odds are you meant the State of Washington

unless there is a mistake in the problem, miscopied or a mistake in the original problem

as most would interpret "for Washington" as Washington DC

4036-1449 = 2587 km left to go for both cars

they're both just 36% of the way there to Seattle