Randle can trim 4 bushes per hour and Billy can trim 5 bushes per hour

Question

Randle can trim 4 bushes per hour and Billy can trim 5 bushes per hour. If Randle and Billy must work together to trim all 50 bushes in the park and each person can trim for a maximum of 6 hours, what is the least amount of time that Billy must trim?

A. 4 hours and 48 minutes
B. 5 hours
C. 5 hours and 12 minutes
D. 5 hours and 33 minutes
E. 6 hours

A. 4 hours and 48 minutes
B. 5 hours
C. 5 hours and 12 minutes
D. 5 hours and 33 minutes
E. 6 hours

khushbumodi · Answer

For Billy to work for least number of hours, Randle must work for maximum hours

Thus he will trim 4*6 24 bushes in 6 hours 
Out of 50 bushes, 24 have been trimmed by Randle. So Billy has to do the rest of the work (26) bushes 
26/5 = 5hrs 12 minutes 
Hence, C

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pushpitkc · Answer

For billy to take the lowest time, randle must first exhaust all his 6 hours and then billy should start his work.

Given data
randle's rate : 4 bushes/hr
billy's rate : 5 bushes/hr
Total bushes : 50

After randle completes his time(6 hours), only 26 bushes remain. Hence, billy will take 
26 bushes/(5 bushes/hour)= 5.2hours or 5 hours and 12 minutes(Option C)

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mohshu · Answer

Randle must work for maximum hours

he trims 4*6 = 24 bushes in 6 hours 
Out of 50 bushes, 24 have been trimmed by Randle. Billy has to do 26 bushes 
26/5 = 5hrs 12 minutes 
ANS C

ScottTargetTestPrep · Answer

We are given that Randle can trim 4 bushes per hour. If he trims for 6 hours (the maximum time he can trim), then he will have trimmed 4 x 6 = 24 bushes. Thus, there are 50 - 24 = 26 bushes left for Billy to trim.

Since Billy can trim at a rate of 5 bushes per hour, the time he will have to trim is:

26/5 = 5 ⅕ = 5 hours and 12 minutes

Answer: C

AqsaGhori · Answer

Randle=4 bush/hour
Billy=5 bush/hour
total=50 bushes
time allowed to finish work=6 hour
since we are giving favor to billy and he will do least work so first calculate how much at max rindle can do alone
randle=4*6=24 bushes
so billy need to cut 26 bush atleast 
billy work speed=26/5 bush per hour=5 hour 12 min
Option C

bumpbot · Answer

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Randle can trim 4 bushes per hour and Billy can trim 5 bushes per hour

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Randle can trim 4 bushes per hour and Billy can trim 5 bushes per hour

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