Each of 10 machines works 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 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
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GMAT數學題!請數學達人指點!
2009-06-21 8:30 pm
回答 (1)
2009-06-21 9:03 pm
✔ 最佳答案
The total workload=(10(16)=160The time required
=The total workload/the number of machines
=160/8
=20 hours
收錄日期: 2021-04-22 00:45:55
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