If anyone can explain how to work through this problem, that would very helpful. thanks!
Six machines, each working at the same constant rate, together can complete a certain job in 12 days. How many additional machines, each working at the same constant rate, will be needed to complete the job in 8 days?
a)2
b)3
c)4
d)6
e)8
Answer:
b)3
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if 6 machines takes 12 daysgxj007 wrote:If anyone can explain how to work through this problem, that would very helpful. thanks!
Six machines, each working at the same constant rate, together can complete a certain job in 12 days. How many additional machines, each working at the same constant rate, will be needed to complete the job in 8 days?
a)2
b)3
c)4
d)6
e)8
Answer:
b)3
1 machine will take 12/6=2 days
2 days are taken by 1 machine to finish the job
therfore, 8 days are taken by (1/2)*8=4 machine
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(machine1 x time1/job2)=(machine1xtime1/job1)gxj007 wrote:If anyone can explain how to work through this problem, that would very helpful. thanks!
Six machines, each working at the same constant rate, together can complete a certain job in 12 days. How many additional machines, each working at the same constant rate, will be needed to complete the job in 8 days?
a)2
b)3
c)4
d)6
e)8
Answer:
b)3
6x12/1=8M
m=9
so additional machines = 9-6=3 -->D
you got this man!