RSOHAL wrote:

Working at their respective constant rates, machine A makes 100 copies in 12 minutes and machine B makes 150 copies in 10 minutes. If these machines work simultaneously at their respective rates for 30 minutes, what is the total number of copies that they will produce?

(A) 250

(B) 425

(C) 675

(D) 700

(E) 750

Machine A can produce 100 *30/12= 250 copies

And, Machine B can produce 150* 30/10= 450 Copies

Total producing 700 Copies.

D is the answer

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