Problem Solving (PS) | Re: Running at the same constant rate, a identical machines

easier to get confused without the appropriate highlight in the question part -
Running at the same constant rate, a identical machines can produce a total of 120 bolts per minute.

a machines -> 120
1 machine -> 120/a
4 machines -> (120*4)/a

above is all per minute, so for 5 minutes -
(120*4*5)/a = 2400/a

E

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