Two persons A and B can complete a piece of work in 18 days and 24 days respectively. If they work together, what part of the work will be completed in 2 days?
Options:
(A) 7/36
(B) 9/35
(C) 4/37
(D) 8/35
(E) 5/3
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A's one day's work = 1/18
B's one day's work = 1/24
(A + B)'s one day's work = 1/18 + 1/24 = 7/72
The part of the work completed in 3 days = 2 (7/72) = 7/36. So the answer is: (A).
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Ravi can do a piece of work in 15 days while Prakash can do it in 30 days. In how many days will they finish it together?
Options:
(A) 11 days
(B) 9 days
(C) 8 days
(D) 12 days
(E) 10 days
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1/15 + 1/30 = 3/30
10/1 = 10 days So the answer is: (E).
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The sticks of same length are used to form a triangle as shown below.If 87 such sticks are used then how many triangles can be formed?
Options:
(A) 43
(B) 44
(C) 45
(D) 465
(E) 47
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First triangle is formed by using 3 sticks, but any subsequent triangle may be formed by using 2 sticks. Therefore, If 1st triangles uses 3 sticks, Remaining sticks = 87 - 3 = 84. With these 84, we can form 42 triangles. So total = 42 + 1 = 43 So the answer is: (A).
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