The speed of a boat in still water is 30kmph and the speed of the current is 20kmph. Find the speed downstream and upstream?
Options:
(A) kmph
(B) kmph
(C) kmph
(D) kmph
(E) kmph
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Speed downstream = 30+ 20 = 50 kmph
Speed upstream = 30 - 20 = 10 kmph So the answer is: (B).
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The average of seven numbers is 26. The average of first three numbers is 14 and the average of last three numbers is 19. What is the middle number?
Options:
(A) 25
(B) 83
(C) 29
(D) 32
(E) 34
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The total of seven numbers = 7X26 = 182
The total of first 3 and last 3 numbers is = 3 X 14+3 X 19 = 99
So, the middle number is (182 - 99 ) = 83 So the answer is: (B).
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How many two-digit numbers satisfy this property.: The last digit (unit's digit) of the square of the two-digit number is 3 ?
Options:
(A) 4
(B) 0
(C) 3
(D) 2
(E) 1
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A number ending with 3 can never be a perfect square. So the answer is: (B).
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