One copy machine can make 20 copies a minute, and a second copy machine makes 10 copies a minute. If the two copiers work together, how long would it take them to make 900 copies?
Options:
(A) 10 minutes
(B) 20 minutes
(C) 25 minutes
(D) 30 minutes
(E) 35 minutes
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Total work done by both machines in a minute = 20 + 10 = 30 copies
Total number of copies required = 900
Time = 900/30 = 30 mins So the answer is: (D).
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A no. x when divided by 221 gives a remainder 43, what remainder will beobtained by dividingthe same no.17?
Options:
(A) 1
(B) 4
(C) 9
(D) 11
(E) 13
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221 + 43 = 264/17 = 9 (Remainder) So the answer is: (C).
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The salary of a worker is first increased by 30% and afterwards reduced by 30%. What is net change in his salary?
Options:
(A) 910% increase
(B) 10% increase
(C) 9% decrease
(D) 12% decrease
(E) 15% increase
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(30 * 30)/100 = 9% decrease So the answer is: (C).
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