n(n2 - 1) = n(n - 1) (n + 1). If n is a an odd number and n > 1, then either of (n + 1) and (n - 1) is a multiple of 4 and
the other is a multiple of 2. Also, since (n - 1), n, (n - 1) are three consecutive numbers, one of them must be a
multiple of three. thus the product has to be a multiple of (4 ? 3 ? 2) = 24.
Each question contains six statements followed by four sets of combinations of three. Choose the set in which the statements are logically related.
Q. No. :
2
Question :
1. Some spanials are not good hunters.
2. All spanials are gentle dogs.
3. No good hunter is a gentle dog.
4. All gentle dogs are spanials.
5. Some gentle dogs are not good hunters.
6. Some spaniels are good hunters.
A :
125
B :
346
C :
265
D :
561
Answer: A
Q. No. :
3
Question :
1.Some women are undependable.
2.All women are undependable.
3. No undependable person is fit for employment.
4. All who are fit for employment are women.
5. Some undependable persons are fit for employment.
6. No one who is fit for employment is a woman.
A :
236
B :
165
C :
246
D :
631
Answer: A
Q. No. :
4
Question :
1. All introverts are paid well.
2. All doctors are paid well.
3. Some of those who are paid well are not doctors.
4. No doctor is an introvert.
5.Some introverts are doctors.
6. Some introverts are paid well.
A :
125
B :
563
C :
463
D :
421
Answer: C
Q. No. :
5
Question :
Thickness of a rectangular box is P units. Its breadth is 4 more than the thickness and length 2 more than the breadth. What is the volume of the box.?
Let original radius = r , original area = p *r2 New radius = 3r/4 m, New area = p (3r/4)2
= p *r2/16
Decrease in area = p* r2 - 9p r2/16
= 7 p r2/16
Decrease % =m 7 p* r2 * 1/ p r2* 100
= 43.75%
Q. No. :
7
Question :
The speed of a railway engine is 42 Km per hour when no compartment is attached, and the reduction in speed is directly proportional to the square root of the number of compartments attached. If the speed of the train carried by this engine is 24 Km per hour when 9 compartments are attached, the maximum number of compartments that can be carried by the engine is:
reduction in speed r = k√x where x is number of compartments v = 42 - k√x kmph 24 = 42 - k√9 or, k = 18/3 = 6 For max number of compartment v >0 or, 42 - 6√x > 0 or, 6√x < 42 or, √x < 7 or, x < 49 So, x = 48