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Question 1201033: A car and a bust left regina at the same time. the car drove 480km west to calgary. the bus drove 570 km east to winnipeg. the bus travelled 15 km/hr faster than the car. they arrived at the destinations at the same time. what was the speed of the car ? what was the speed of the bus ?
Found 4 solutions by mananth, greenestamps, ikleyn, josgarithmetic:
Answer by mananth(16946)   (Show Source):
You can put this solution on YOUR website! Let car speed be x km/h
Bus speed = (x+15) km/h
Time taken by both same
Time = Distance / speed
480 / x = 570/(x+15)
Cross multiply
480*(x+15) = 570 x
480 x + 7200 = 570x
7200 = 570x -480x
7200 = 90x
x = 7200/90
x = 80
Speed of car = 80 km/h
Speed of bus = 80 +15 = 95 km/h
Answer by greenestamps(13200)  (Show Source):
You can put this solution on YOUR website!
The other tutor showed one formal algebraic method for solving the problem.
If formal algebra is not required, here is a quick and easy informal solution.
The times for the two vehicles are the same; so the difference in distances is equal to the difference in speeds, multiplied by that amount of time.
The difference in distances was 570-480 = 90 km; the difference in speeds was 15 km/hr. That means the time for both vehicles was 90/15 = 6 hours.
So the speed of the car was 480/6 = 80 km/hr and the speed of the bus was 570/6 = 95 km/hr.
ANSWERS:
car 80 km/hr
bus 95 km/hr
Answer by ikleyn(52793)  (Show Source):
You can put this solution on YOUR website! .
A car and a bust left regina at the same time. the car drove 480km west to calgary. the bus drove 570 km east to winnipeg.
the bus travelled 15 km/hr faster than the car. they arrived at the destinations at the same time. what was the speed of the car ?
what was the speed of the bus ?
~~~~~~~~~~~~~~~~~
Although the problem's composer points that the car and the bus move in opposite
directions, this fact does not matter, does not play any role and, therefore,
does not make any sense in this problem.
It is EXCESSIVE and is NON-NECESSARY; so, for a reader, it is better to ignore this information.
This wording in the problem is far from to be perfect, is unprofessional and only confuses a reader.
Answer by josgarithmetic(39618)  (Show Source):
You can put this solution on YOUR website!
SPEED TIME DISTANCE
CAR r 480/r 480
BUS r+15 570/(r+15) 570
The description is that the time quanties are equal.
Another way is to give a variable to the speed of the BUS.
If b, speed of bus, then
 ------simplify and solve for b.
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