question: If there are 4 seats and two students, in how many ways can they be seated?
Options:
(A) 12
(B) 6
(C) 8
(D) 16
(E) 10
answer: Stream of consciousness: No. of ways of choosing 2 chairs out of 4 chairs on which two students will sit = 4C2 = 6
No. of ways of 2 people sitting on selected chairs = 2!
Total ways of making 2 people sit on 2 of 4 chairs = 4C2*2! = 6*2 = 12 The answer is (A).

q: Find the value of y from (12)^3 x 6^4 432 = y?
Options:
(A) 2560
(B) 3400
(C) 3690
(D) 4500
(E) 5184
a: Stream of consciousness: Given Exp. = (12)3 x 64 = (12)3 x 64 = (12)2 x 62 = (72)2 = 5184
432 12 x 62 The answer is (E).

question: A Train requires 10 seconds to pass a pole while it requires 30 seconds to cross a stationary train which is 600 mtrs long. Find the speed of the train.
Options:
(A) 110 kmph
(B) 120 kmph
(C) 108 kmph
(D) 100 kmph
(E) 98 kmph
answer: Stream of consciousness: In 10s the train crosses the pole and in 30 sec the train crosses one more stationary train
In 20 sec the train travels a distance of 600 mtrs
Speed = 600/20 = 30 m/s = 30 (3600/1000) = 30 * 18/5 = 108 kmph The answer is (C).

q: A teacher has to choose the maximum different groups of three students from a total of six students. Of these groups, in how many groups there will be included in a particular student?
Options:
(A) 6
(B) 8
(C) 10
(D) 12
(E) 15
a: Stream of consciousness: If students are A, B, C, D, E and F; we can have 6C3 groups in all. However, if we have to count groups in which a particular student (say A) is always selected we would get 5C2 = 10 ways of doing it. The answer is (C).

question: A certain car uses 12 gallons of gasoline in traveling 300 miles. In order for the car to travel the same distance using 10 gallons of gasoline, by how many miles per gallon must the car's gas mileage be increased?
Options:
(A) 2
(B) 4
(C) 5
(D) 8
(E) 10
answer: Stream of consciousness: 300/10 = 30. The difference is 30 - 25 = 5. The answer is (C).

question: 189. The inside dimensions of a rectangular wooden box
are 10 inches by 12 inches by 14 inches. A cylindrical
canister is to be placed inside the box so that it stands
upright when the closed box rests on one of its six
faces. Of all such canisters that could be used, what is
the radius, in inches, of the one that has maximum
volume?
Options:
(A) 3
(B) 4
(C) 5
(D) 6
(E) 8
answer:
Stream of consciousness: Since the radius is squared, the biggest volume cylinder will have the biggest possible radius. To achieve that, let the smaller dimension of the rectangular box be the height. So, it will have 14x12 width x length. The biggest cylinder must fit both dimensions, so it must have at most a diameter of 12, so the radius will be 6. The answer is (D).