Bunuel wrote:
Machine A and machine B working at their constant respective rates produced 50 components in 20 minutes. How much time, in minutes, would it have taken machine B working alone at its constant rate to produce 50 components?
(1) Machine A produced 10 fewer components than did machine B.
(2) The rate at which machine B works is 50 percent faster than the rate at which machine A works.
A+B are producing 50 components in 20 minutes.
(1) A produced 10 fewer than B, this means A produced 20 components in 20 minutes while B produced 30 components in 20 minutes. So if B produces 30 in 20 minutes, it produces 1.5 components per minute and thus we can find the time required to produce 50 = 50/1.5 minutes. Sufficient.
(2) So if A produces 'x' components per minute, B produces '1.5x' components per minute. So in 1 minute, A+B produce = x+1.5x = 2.5x components. Thus in 20 minutes they produce = 20*2.5x = 50x components.. but this is given as 50 only. So x=1. Thus A produces 1 per minute while B produces 1.5 per minute. This data now becomes same as in first statement. So Sufficient.
Hence
D answer