Chris travels for a certain length of time at 40 miles per hour and Donny travels for the same length of time at 60 miles per hour. what is the average speed?
50
isnt it greater than 50?
im not sure im not an actual tutor but i just averaged the two 40+60= 100 divided by 2= 50
I think that is the trick and you are not supposed to do that. Thanks though for trying!
Let the time at 40 mph be t
distance covered at 40 mph = 40t
distance covered at 60 mph = 60t
total distance = 40t+60t
total time = 2t
avg speed = total distance/total time
= 100t/(2t) = 50
No trick here,
had it said, Chris travels the same distance at 40, and then at 60, you would have a "trick " question.
=
In this case, he answer actually is 50. Consider. Average speed is total distance divided by total time.
Without loss of generality, we can assume they each drove for 1 hour. In each hour, Chris goes 40 miles, and Donny goes 60 miles. Total distance: 100 mi. Total time: 2 hours. Average speed: 50 mph.
Usually there is a "trick" involved, making some constraints that alter the answer. In this case, the problem is surprisingly uninvolved. In fact, I wonder whether it was properly posted.