Rationale: Rate upstream = (1/20 *60) = 3 kmph
Rate dowm stream = 1/12 * 60 = 5 kmph
Rate of the current = (5-3) = 1 kmph
The answer: (A)
Question: A boat moves upstream at the rate of 1 km in 20 minutes and down stream 1 km in 12 minutes. Then the speed of the current is :
Options:
(A) 1 kmph
(B) 2 kmph
(C) 3 kmph
(D) 2.5 kmph
(E) 3.5 kmph
Reasoning: Using question number 11 and 12, we get the probability as
1 - (1/36 + 5/9) = 5/12
Ans: (B)
Question: Three 6 faced dice are thrown together. The probability that exactly two dice show the same number on them is ?
Options:
(A) 5/16
(B) 5/12
(C) 5/19
(D) 5/17
(E) 5/15
Rationale: Mode of a set is the data point that is repeated the most number of times. In the set given, 7 is repeated.
The answer: (C)
Question: What is the Mode of the following data set R- {1,2,7,9,6,6,7,7}
Options:
(A) 1
(B) 2
(C) 7
(D) 6
(E) 9
Reasoning: 1/2:1/3:1/4 = 6:4:3
Ram = 6/13 * 3250 = 1500
Shyam = 4/13 * 3250 = 1000
Mohan = 3/13 * 3250 = 750
Ans: (A)
Question: If Rs.3250 be divided among Ram, Shyam and Mohan in the ratio of 1/2:1/3:1/4 then the share of each are?
Options:
(A) Ram = Rs.1500, Shyam = Rs.1000, Mohan = Rs.750
(B) Ram = Rs.2500, Shyam = Rs.500, Mohan = Rs.250
(C) Ram = Rs.1200, Shyam = Rs.1300, Mohan = Rs.750
(D) Ram = Rs.3500, Shyam = Rs.500, Mohan = Rs.250
(E) None
Rationale: 8/9 + 6/x = 1
X = 54 days
The answer: (D)
Question: A can do a piece of work in 9 days. When he had worked for 2 days B joins him. If the complete work was finished in 8 days. In how many days B alone can finish the work?
Options:
(A) 18
(B) 77
(C) 66
(D) 54
(E) 12
Rationale: Maximum points of intersection between n different circles = n*(n - 1) = 10*9 = 90
The answer: (A)
Question: There are different 10 circles. What is the number of the greatest possible points with which the circles intersect?
Options:
(A) 90
(B) 100
(C) 110
(D) 180
(E) 200