Bunuel
An employee at a company was given the task of making a large number of copies. He spent the first 45 minutes making copies at a constant rate on copier A, but copier A broke down before the task was completed. He then spent the next 30 minutes finishing the task on copier B, which also produced copies at a constant rate. How many total minutes would the task have taken had copier A not broken down?
(1) Copier A produced twice as many copies in its first 5 minutes of operation as copier B produced in its first 15 minutes.
(2) Copier B produces 10 copies per minute.
(1) Copier A produced twice as many copies in its first 5 minutes of operation as copier B produced in its first 15 minutes.
In 5 minutes A makes = 2x copies
In 45 minutes A will makes = 18x copies
In 15 minutes B makes = x copies
In 30 minutes b will make e= 2x copies
WORK IS FINISHED
Therefore total work that was remaining when A broke down was only 2x
We know that A completed 18x work in 45 minutes
therefore we know it would have completed 2x work in (45/18 )*2 = 5 minutes
SO A would have completed the task in 45 + 5 = 50 minutes
SUFFICIENT
(2) Copier B produces 10 copies per minute.
B produced 30*10 = 300 copies
We do not know how many total copies are there to make:-
Therefore we cannot know how many copies A made:-
therefore we cannot know the rate of A.
therefore we cannot know total time that A would have taken
INSUFFICIENT
ANSWER IS A