Two cars set off from the same point to travel the same journey.
The first car has a start of seven minutes before the second car leaves.
If the first car travels at 60 km/h and the second car travels at 90 km/h, how many kilometres will be travelled when the cars are level?
2007-10-31 14:35:59 · 2 answers · asked by CubeScience 3 in Entertainment & Music ➔ Jokes & Riddles
If a car is going 60 km an hour it is going 1 km a minute.
A car going 90 km is going 1.5 km a minute.
t is the time traveled when the cars are level.
1t +7=1.5t
subtract t from both sides
7=.5t
Divide by 1/2 (.5)
t=14 minutes
If the cars travel for 14 minutes before they are level
The car that is traveling 60 k/h will go 14 km (14x1)
The car that is traveling 90 k/h will go 21 km (14x1.5)
14 and 21 is 35.
So the combined distance of the cars is 35 km.
2007-10-31 15:10:07 · answer #1 · answered by Truth 7 · 0⤊ 0⤋
21km
2007-10-31 15:05:05 · answer #2 · answered by witch2order 5 · 0⤊ 0⤋