plugging in is the best approachbacali wrote:OA: E
let the distance be 100
and x percentis 50%
thus,
first half time = 5/4
second half will be = 5/6
average speed = total distance/total time
100/( 5/4+ 5/6) = 1200/25
which is E.
hope that helps..
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sudhir3127
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cramya
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Similar approach
Take x distance as 40 since the first speed is 40 miles/hr to find the time i.e 40/40=1hr
Take remaining distance as 60 speed = 60/60=1 hr
Avg speed = total distance travelled/total time taken
= 100/2 = 50 miles/hr
Only E will work (i.e give 50 miles/hr as the answer) if u plug in 40 for x
Take x distance as 40 since the first speed is 40 miles/hr to find the time i.e 40/40=1hr
Take remaining distance as 60 speed = 60/60=1 hr
Avg speed = total distance travelled/total time taken
= 100/2 = 50 miles/hr
Only E will work (i.e give 50 miles/hr as the answer) if u plug in 40 for x
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logitech
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if x = 0 %
it means that that the average speed is 60!
and when x = 100% the V = 40
Extremes are your friends. Hangout with them!
Hence, E
it means that that the average speed is 60!
and when x = 100% the V = 40
Extremes are your friends. Hangout with them!
Hence, E
LGTCH
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