M4maths Previous Puzzles

04 Aug 2021 Series

What will the next number of following series..
35 26 19 14 ?

OPtion

1) 12
2) 13
3) 10
4) 18
5) 8
6) 15
7) 9
8) 20
9) 11
10) None of the above

Solution

35 26 19 14 ?

difference in numbers is reducing by 2.
i.e. 9,7,5,3

35-9=26
26-7=19
19-5=14
14-3=11

Correct Option: 9 Best Solution (0)

03 Aug 2021 Cost

If 5 kg apples, 6 kg oranges and 2 keg potato cost rupee 186 and 13 kg apples, 6 kg orange and 4 kg potato cost rupee 288. what would be the cost of 1kg potato, 2kg orange and 3 kg apple

OPtion

1) 79
2) 59
3) 52
4) 67
5) 65
6) 77
7) 89
80 145
9) 82
10) None of the above

Solution

Solving given conditions, we get
cost of apple = Rs 12 per kg
cost of orange .. Rs 20 per kg.
cost of potato .. Rs 3 per kg
cost of 1kg potato, 2kg orange and 3 kg apple = 3+40+36=Rs 79.

Correct Option: 1 Best Solution (3)

02 Aug 2021 Purchasing

According to a scheme a shopkeeper gives 50%, 40%, 30% in 3 purchasing's. these purchasing cost 1500, 2700, 3500. minimum total bill would be?

OPtion

1) 3280
2) 3200
3) 3350
4) 4420
5) 4846
6) 4400
7) 2250
8) 2430
9) 5800
10) None of the above

Solution

Max discount are
3500 50% = 1750
2700 40% = 1080
1500 30% = 450

So the total bill amount is = 7700 - 3280 = 4420

Correct Option: 4 Best Solution (3)

30 Jul 2021 PROBABILITY

There are 5 switches in a board. In these 5 switches 1 is attached with the fan. A person has to start the fan in 2 attempts only. Probability of success will be

OPtion

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

Solution

Probability of success in first attempt = 1/5
Probability of success in second attempt after first unsuccessful attempt = (4/5)*(1/4) = 1/5
so total probability = 1/5 + 1/5 = 2/5

Correct Option: 2 Best Solution (3)

29 Jul 2021 Subject

The % obtained by a student is 74. If we take % on the basis of 4 subjects (leaving the marks of fifth subject) then % is 76. How many marks, he got in the fifth subject.

OPtion

1) 69
2) 66
3) 70
4) 71
5) 75
6) 79
7) 59
8) 56
9) 65
10) None of the above

Solution

average of 4 sub =76
so total marks =4*76=304
average of 5 sub=74
so total marks=5*74=370
so mark of 5th sub=370-304=66

Correct Option: 2 Best Solution (3)

28 Jul 2021 Find the probability

What will be the probability to form word NOTEBOOK by using letters B,E,K,N,O,O,O and T. If you have to make arrangement of E,N,O and T first, after then you have to arrange B,K,O and O.

OPtion

1) 1/122
2) 1/266
3) 1/288
4) 1/166
5) 3/322
6) 1/323
7) 1/12
8) 1/222
9) 1/322
10) none of these

Solution

probability to form word NOTE from N,O,T,E is
1/4 *1/3 *1/2*1= 1/24
probability to form word BOOK from B,O,O,K is
1/4*2/3*1/2*1= 1/12


probability to form word NOTEBOOK by using letters B,E,K,N,O,O,O and T. If you have to make arrangement of E,N,O and T first, after then you have to arrange B,K,O and O. = (1/24)*(1/12) = 1/288

Correct Option: 3 Best Solution (0)

27 Jul 2021 Age

The age of a man is thirty five years and seven and half a month. What is its age in decimal representation?

OPtion

1) 35.72
2) 35.75
3) 35.5
4) 35.71
5) 35.712
6) 35.625
7) 35.705
8) 35.075
9) 35.621
10) None of the above

Solution

seven and half a month= 15/2 months = 15/24 years
= 0.625 years

so age is 35.625 years

Correct Option: 6 Best Solution (4)

26 Jul 2021 Combination

How many numbers of five digits can be formed by using 1, 2, 3, 4, 5, if 4 is necessarily taken at hundred's place and 2 is not allowed at unit's place. Repetition of numbers is not allowed.

OPtion

1) 72
2) 16
3) 12
4) 18
5) 96
6) 24
7) 60
8) 30
9) 15
10) None of the above

Solution

Keeping 4 fixed at 100th position.
so there are 4 digits left.
Out of which 2 can not be placed in units place.
permutation of units place is 3.
permutation of 10000th place is 3
permutation of 1000th place is 2 .
permutation of 100 place is 1
permutation of 10th place = 1
So total permutation - 3 X 2 X 3 X 1 X 1= 18

Correct Option: 4 Best Solution (2)

23 Jul 2021 Paper

The thickness of a paper is 0.7 mm. Number of papers in a rim of thickness 26.6 cm. are

OPtion

1) 38
2) 2060
3) 22060
4) 206
5) 380
6) 3800
7) 308
8) 1862
9) 450
10) None of the above

Solution

26.6 cm. = 266 mm.

Hence number of pages = 266 / 0.7 = 380

Correct Option: 5 Best Solution (5)

22 Jul 2021 Number

A number (x) is 3 less than the thrice of other number (y) and the sum of their squares is 97.
The values of x and y are respectively?

OPtion

(1) 8,4
(2) 4,9
(3) 4,8
(4) 9,4
(5) 3,9
(6) 9,3
(7) 5,9
(8) 9,5
(9) 8,5
(10) None of the above

Solution

x = 3y - 3 and x^2 + y^2 = 97
On solving these two equations
x = 9 and y = 4

Correct Option: 4 Best Solution (4)