If 3 machines produce x
rods/minute, then this implies that one machine would do 1/3 of the work: that is, x/3
rods/minute.
If we know the rate for one machine, we can find the rate for 8 machines, which is simply 8 times the rate for one:
x/3
rods/minute * 8 = 8x/3
rods/minuteThen
work done = speed of work * time:
number of
rods = 8x/3
rods/minute * 5
minutes==>
rods = 40x/3
Answer A.Here, note that we could easily take the rate for 3 machines and multiply by 8/3 to get the rate for 8 machines and this would get the same answer. I did it in stages, but you can do it more quickly if that's comfortable.
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