单选题It took 12 men 4 hours to build a structure. Working at the same rate, how many additional men could have been hired in order for the job to have taken 1 hour less?AtwoBthreeCfourDsix.Eeight
单选题
It took 12 men 4 hours to build a structure. Working at the same rate, how many additional men could have been hired in order for the job to have taken 1 hour less?
A
two
B
three
C
four
D
six.
E
eight
参考解析
解析：
The number of men working and the hours needed for the men to complete the job are inversely related. If x represents the number of additional men needed to complete the job in 3 hours, then 4 ×12=3(12+x), x=4.
The number of men working and the hours needed for the men to complete the job are inversely related. If x represents the number of additional men needed to complete the job in 3 hours, then 4 ×12=3(12+x), x=4.
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