Working alone, Printers X, Y, and Z can do a certain printing job, consisting of a large number of pages, in 12, 30, and 40 hours, respectively. What is the ratio of the time it takes Printer X to do the job, working alone at its rate, to the time it takes Printers Y and Z to do the job, working together at their individual rates?
Options:
(A) 4/11
(B) 1/2
(C) 15/22
(D) 120/7
(E) 11/4
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P1 takes 12 hrs
Rate for P2P3 together = 1/30 + 1/40 = 7/120
Therefore they take 120/7
Ratio = 120/7 = So the answer is: (D).
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A man purchased 3 blankets @ Rs.100 each, 5 blankets @ Rs.150 each and two blankets at a certain rate which is now slipped off from his memory. But he remembers that the average price of the blankets was Rs.154. Find the unknown rate of two blankets?
Options:
(A) 420
(B) 550
(C) 490
(D) 450
(E) 457
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10 * 154 = 1540
3 * 100 + 5 * 150 = 1050
1540 1050 = 490 So the answer is: (C).
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K-numbers are positive integers with only 2's as their digits. For example, 2, 22, and 222 are K-numbers. The K-weight of a number n is the minimum number of K-numbers that must be added together to equal n. For example, the K-weight of 50 is 5, because 50 = 22 + 22 + 2 + 2 + 2. What is the K-weight of 650?
Options:
(A) 10
(B) 11
(C) 12
(D) 13
(E) 14
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650 = 2*222 + (22*9) + 4*2
K weight of 600 = 2 +9+2 = 13 So the answer is: (D).
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