M4maths Previous Puzzles

08 Dec 2011 Find the difference

Difference between 4 and (1.333+1.333+1.333) is

OPtion

1) 10^-1
2) 10^-2
3) 10^-3
4) 10^-5
5) 10^-6
6) 10^-7
7) 10^-4
8) 10^-8
9) 10^-9
10) none of these

Solution

4-(1.333+1.333+1.333) = .001 = 10^-3

Correct Option: 3 Best Solution (22)

07 Dec 2011 letter

By using the letters A, E, O, E, P, Q, T, S, how many words can be formed, if we have to place all the vowels in even places

OPtion

1) 144
2) 2
3) 288
4) 12
5) 24
6) 576
7) 1
8) 40320
9) 20160
10) none of these

Solution

total no. of methods = (4*3*2*1)*(4*3*2*1)/2 = 288

Correct Option: 3 Best Solution (2)

06 Dec 2011 acceleration

The formula for finding the acceleration of the car is
a = (product of sum and difference of velocities)/2(total distance)
In a journey of 2 km, initial and final velocities of the car are 18 km/hr and 90 km/hr respectively. Calculate the acceleration.

OPtion

1) 0.2 m/s^2
2) 0.3 m/s^2
3) 0.4 m/s^2
4) 0.5 m/s^2
5) 1944 m/s^2
6) 1956 m/s^2
7) 1998 m/s^2
8) 0.15 m/s^2
9) 0.25 m/s^2
10) none of these

Solution

velocities in m/s are 18*5/18 = 5 m/s and 90*5/18 = 25 m/s
and 2 km = 2000 m
so acceleration = 30*20/2*2000 = 0.15

Correct Option: 8 Best Solution (0)

05 Dec 2011 probability

x*y = .........3 (1)
If x and y are integers from 1 to 20, then probability of x and y to satisfy the condition (1) will be (In blank space of equation (1) minimum number of integers should be one.

OPtion

1) 1/100
2) 1/200
3) 3/200
4) 3/100
5) 7/100
6) 7/200
7) 11/100
8) 11/200
9) 13/100
10) none of these

Solution

possible set of x and y are (1,13), (3,11), (7,9), (7,19), (9,7), (9,17), (11,3), (11,13), (13,1), (13,11), (17,9), (17,19), (19,7), (19,17)
so probability = 14/400 = 7/200

Correct Option: 6 Best Solution (3)

02 Dec 2011 prime

x^4 when divided by 6, will provide as reminder (here x is prime number)

OPtion

1) 1
2) 2
3) 3
4) 4
5) 5
6) 6
7) 7
8) two answers are possible
9) three answers are possible
10) none of these

Solution

2^4 when divided by 6 will provide reminder as 4
3^4 when divided by 6 will provide reminder as 3
for all others reminder will be 1
so three answers are possible

Correct Option: 9 Best Solution (2)

01 Dec 2011 sqrt means square root

The approx sum of numbers sqrt(1), sqrt(2),......, upto sqrt(10) will be

OPtion

1) 22.5
2) 23.4
3) 23.9
4) 24.4
5) 25.8
6) 26.5
7) 27.7
8) 28.8
9) 29.9
10) none of these

Solution

sum = 1+1.414+1.732+2+2.236+2.45+2.65+2.828+3+3.16 = 22.47 = 22.5

Correct Option: 1 Best Solution (0)

30 Nov 2011 word puzzle

If DIWALI-HOLI = 14
then AUGUST-JULY = ?

OPtion

1) 15
2) 17
3) 18
4) 19
5) 21
6) 23
7) 28
8) 30
9) 34
10) none of these

Solution

This question is based on the positional number of any letter in English alphabet.

Correct Option: 5 Best Solution (11)

29 Nov 2011 percentage

x % of y is z, then z % of y is

OPtion

1) (x^2)/y
2) x/y
3) y/(z^2)
4) (z^2)/x
5) (y^2)/x
6) x/(y^2)
7) z/(x^2)
8) x/(z^2)
9) z/y
10) none of these

Solution

x % of y is z implies that xy/100 = z
now z % of y = zy/100 = zy/(xy/z) = (z^2)/x

Correct Option: 4 Best Solution (22)

28 Nov 2011 pair

x, y and z are integers such that y+z<8, x>0, y>0, z>0. How many pairs (x,y) are possible.

OPtion

1) 21
2) 42
3) 84
4) 100
5) 256
6) 1024
7) 64
8) 1380
9) infinite
10) none of these

Solution

You can take any value in the place of x

Correct Option: 9 Best Solution (0)

25 Nov 2011 average

The average of 5 successive integers is 12.Their product will be

OPtion

1) 134560
2) 154680
3) 165490
4) 213460
5) 234240
6) 236580
7) 240240
8) 283450
9) 324340
10) none of these

Solution

the integers will be 10, 11, 12, 13, 14
their product = 240240

Correct Option: 7 Best Solution (34)