Can someone help map out the solution to this problem?
Each of 10 machines work at the same constant rate doing a certain job. the amount of time needed by the 10 machines working together to complete the job is 16 hours. How many hours is needed if only 8 of the machines, working together, were used to complete the job?
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Here's the complete question:
So, we can say that the job requires a total of 160 MACHINE HOURS (10 machines each working 16 hours = 160 machine hours)
How many hours would be needed if only 8 of the machines, working together, were used to complete the job?
We need to divide the work of 160 machine hours among the 8 machines.
160/8 = 20 hours
Answer: B
Cheers,
Brent
Here's a similar question to try: https://www.beatthegmat.com/work-problem-t275195.html
The amount of the time needed by the 10 machines working together, to complete the job is 16 hours.Each of 10 machines works at the same constant rate doing a certain job. The amount of the time needed by the 10 machines working together, to complete the job is 16 hours. How many hours would be needed if only 8 of the machines, working together, were used to complete the job?
A. 18
B. 20
C. 22
D. 24
E. 26
So, we can say that the job requires a total of 160 MACHINE HOURS (10 machines each working 16 hours = 160 machine hours)
How many hours would be needed if only 8 of the machines, working together, were used to complete the job?
We need to divide the work of 160 machine hours among the 8 machines.
160/8 = 20 hours
Answer: B
Cheers,
Brent
Here's a similar question to try: https://www.beatthegmat.com/work-problem-t275195.html
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*edit: no idea*
Last edited by Matt@VeritasPrep on Tue Mar 10, 2015 11:34 pm, edited 1 time in total.
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10 machines complete the job in 16 hours. So each hour they do 1/16 of the job.Each of 10 machines works at the same constant rate doing a certain job. The amount of the time needed by the 10 machines, working together, to complete the job is 16 hours. How many hours would be needed if only 8 of the machines, working together, were used to complete the job?
A. 18
B. 20
C. 22
D. 24
E. 26
8 machines will do 8/10 of the work that 10 do per hour. So the hourly rate of 8 machines is 8/10 * 1/16 = 8/160 = 1/20
If the 8 machines complete 1/20 per hour, they need 20 hours to complete the job.
Choose B.
Marty Murray
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Perfect Scoring Tutor With Over a Decade of Experience
MartyMurrayCoaching.com
Contact me at [email protected] for a free consultation.