q: In wardrobe Marry has 3trousers. One of them is grey the 2nd blue and the 3rd brown. In his wardrobe he also has 4shirts. One of them is grey and the other 3are white. He openshiswardrobe in the dark and pick out one shirt trouser pair without examination the color. What is the likelihood that neither the shirt nor the trouser is grey?
Options:
(A) 1/2
(B) 2/3
(C) 3/5
(D) 4/7
(E) 4/9
a: Probability that trouser is not grey = 2/3
Probability that shirt is not grey = 3/4
Required probability = 2/3 x 3/4 = 1/2 The answer is (A).
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q: A man rows his boat 70 km downstream and 45 km upstream, taking 2 1/2 hours each time. Find the speed of the stream?
Options:
(A) 1 kmph
(B) 6 kmph
(C) 5 kmph
(D) 8 kmph
(E) 7 kmph
a: Speed downstream = d/t = 75/(2 1/2) = 28 kmph
Speed upstream = d/t = 45/(2 1/2) = 18 kmph
The speed of the stream = (28 - 18)/2 = 5 kmph The answer is (C).
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q: There are 1000 doors that are of the open-close type. When a person opens the door he closes it and then opens the other. When the first person goes he opens-closes the doors in the multiples of 1 i.e., he opens and closes all the doors. when the second goes he opens and closes the doors 2, 4 6 8 respectively. Similarly when the third one goes he does this for 3 6 9 12 15th doors respectively. Find number of doors that are open at last.
Options:
(A) 29
(B) 31
(C) 32
(D) 24
(E) 21
a: 31. only the perfect squares between 1 to 1k The answer is (B).
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q: A no.when divided by 125 gives a remainder 40, what remainder will be obtainedby dividingthe same no.15?
Options:
(A) 10
(B) 11
(C) 12
(D) 13
(E) 14
a:
125 + 40 = 165/15 = 11 (Remainder) The answer is (B).
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