Car X traveled from City A to city B in 30 minutes. What was the avg speed of car X
1. Half the distance of the trip was covered at 50 mph and the other half of the distance was covered at 60 mph
2. Car X traveled 30 miles during the trip
My guess A
OA: D (question is from GMAT express application on iPhone)
My thoughts - 2 does not say anything about speed or time. How on earth does 2 help us.
Car X traveled from City A to city B in 30 minutes ...
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d = r * tdoclkk wrote:Car X traveled from City A to city B in 30 minutes. What was the avg speed of car X
1. Half the distance of the trip was covered at 50 mph and the other half of the distance was covered at 60 mph
2. Car X traveled 30 miles during the trip
My guess A
OA: D (question is from GMAT express application on iPhone)
My thoughts - 2 does not say anything about speed or time. How on earth does 2 help us.
30 = r * .5
60 = r
1 and 2 are SUFFICIENT so D.
IMO D). from 1) you can make one equation with one unknown sufficientdoclkk wrote:Car X traveled from City A to city B in 30 minutes. What was the avg speed of car X
1. Half the distance of the trip was covered at 50 mph and the other half of the distance was covered at 60 mph
2. Car X traveled 30 miles during the trip
My guess A
OA: D (question is from GMAT express application on iPhone)
My thoughts - 2 does not say anything about speed or time. How on earth does 2 help us.
from 2) idem if you know the distance + time (given in the question) you can know the avg
Car X traveled from City A to city B in 30 minutes. What was the avg speed of car XUmar82 wrote:Could someone please write out the formula for statement 1?
Thanks!
1. Half the distance of the trip was covered at 50 mph and the other half of the distance was covered at 60 mph
2. Car X traveled 30 miles during the trip
1) x/50+x/60= 2x/y
note that x/50 is distance/speed=time
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From statement1, can't we just take the average of the 1st half and second half to get average speed instead of applying a formula? Does the question have to read ". Half the distance of the trip was covered at [a constant speed of] 50 mph and the other half of the distance was covered at [a constant speed of] 60 mph " - Note my addition of the word constant speed. I still feel that if constant were not added you can still take the average of both and 1 would be sufficient
Any thoughts?
Any thoughts?