M4maths Previous Puzzles

07 Jul 2021 Business

A business has two steps. In first step, there is 40 % profit in total investment and in second step, there is 12 % loss in the total output after first step. Overall percentage profit in the initial investment will be

OPtion

1) 23.2
2) 24.4
3) 25
4) 25.8
5) 26.2
6) 27.4
7) 27.8
8) 29
9) 32.4
10) none of these

Solution

after first step output = x*1.4
after second step output = x*1.4*0.88 = 1.232*x
so profit percentage = 0.232*x*100/x = 23.2

Correct Option: 1 Best Solution (4)

06 Jul 2021 AVERAGE

The average of first set of 6 numbers is 12, second set of 8 numbers is 14 and third set of 14 numbers is 10. Calculate the average of all the numbers

OPtion

1) 10.95
2) 10.99
3) 11.34
4) 11.57
5) 12.23
6) 12.89
7) 13.45
8) 13.95
9) 14.78
10) none of these

Solution

sum of first set 6 numbers is 12*6 = 72
sum of second set 8 numbers is 14*8 = 112
sum of third set 14 numbers is 14*10 = 140
total sum of 28 numbers is =(72+112+140) = 324
Average of 28 numbers is = 324/28 = 11.57

Correct Option: 4 Best Solution (4)

05 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 not succeeding in 1st attempt = 4/5
Probability of not succeeding in 2nd attempt = 3/4
Probability of not succeeding in 1st two attempts = (4/5)*(3/4) = 3/5
Probability of succeeding in 1st two attempts = 1-3/5=2/5

Correct Option: 2 Best Solution (2)

02 Jul 2021 Banana

A man paid a certain amount to buy 24 dozens banana. If the rate of banana would be 4 rupee more for each dozen, then he bought as many dozens as was the previous rate. Total investment of the man was?

OPtion

1) 480
2) 148
3) 180
4) 200
5) 248
6) 308
7) 360
8) 400
9) 500
10) none of these

Solution

let the cost of 1 dozen = x
then according to the given condition
24 x = x (x+4)
or x = 20
So total investment = 20*24 = 480

Correct Option: 1 Best Solution (2)

01 Jul 2021

The cost (per Kg) of 3 qualities of rice are 45, 42 and 35 respectively. The cost (per Kg) of a mixture of 10 Kg of first, 8 Kg of second and 7 Kg of third will be

OPtion

1) 39.86
2) 39.64
3) 40.46
4) 41.24
5) 42.34
6) 42.38
7) 43.46
8) 43.12
9) 44.42
10) none of these

Solution

10 kg of 1st= 45*10= 450
8 kg of 2nd= 42*8= 336
7 kg of 3rd= 35*7= 245
total rice= 25 kg
total price= 450+336+245=1031
per kg. price= 1031/25
= 41.24 rs.

Correct Option: 4 Best Solution (4)

30 Jun 2021 Linear equation

x + 2y = 9, x and y are non negative integers.
Possible no. of solution pairs are

OPtion

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

Solution

Possible Values of (x,y) are
1) (9,0)
2) (7,1)
3) (5,2)
4) (3,3)
5) (1,4)

Hence Option 5 is the correct answer.

Correct Option: 5 Best Solution (2)

29 Jun 2021 Number

Minimum sum of 5 positive integers on the basis of following conditions
1. 1 is not allowed
2. Two successive integers are not allowed
3. First two prime numbers are not allowed

OPtion

1. 45
2. 41
3. 20
4. 37
5. 40
6. 22
7. 38
8. 43
9. 44
10. None of the above

Solution

1. 1 is not allowed
2. Two successive integers are not allowed
3. First two prime numbers (2,3) are not allowed .
Minimum possible number is 4.
Next number can be 6 only as two successive integers are not allowed.
Under given conditions, Minimum sum of 5 positive integers will be 40 as 4+6+8+10+12=40.

Correct Option: 5 Best Solution (5)

28 Jun 2021 Cost

What will be the cost of 49 Kg ginger at a rate of 49 rupee per Kg it there is a discount of 49% in this purchase.

OPtion

1) 1000
2) 1120.5
3) 1195.5
4) 1224.5
5) 1328
6) 1526.5
7) 1656.5
8) 1770
9) 1800
10) none of these

Solution

Discount of 1 kg ginger= 49*49/100= 24.01
Rate of 1 kg ginger= 49-24.01=24.99
Rate of 49 kg ginger= 49*24.99=1224.5

Correct Option: 4 Best Solution (4)

25 Jun 2021 Train & Speed

The speed of a car is 63 km/h if we don’t let it stop at any point. If the car stops at stops, the speed of the car is 54 km/h. What is the time in minutes that the car stops for per hour?

OPtion

1) 12.00
2) 8.00
3) 10.00
4) 16.00
5) 13.00
6) 7.57
7) 8.57
8) 9.12
9) 11.20
10) None of these

Solution

Distance = Speed × Time.
As the speed of the car is 63 km/h, it will cover 63 km in one hour. Similarly, when we let the car stop, it will cover 54 km/h. Therefore, due to stoppages, it covers 9 km lesser.
Time taken to cover 9 km = [(Distance/Speed)] = [(9/63)] h = (9/63)×60 min = 60/7 min = 8.57 min

Correct Option: 7 Best Solution (0)

24 Jun 2021 arrangement

If 8 cricket teams are participating in a world cup contest, then the number of ways the first, second and third positions may be won is?

OPtion

1) 442
2) 482
3) 380
4) 336
5) 350
6) 399
7) 402
8) 408
9) 378
10) None of the above

Solution

First position can be won by any of the 8 teams
Second position can be won by 7 teams
similarly, third position can be won by 6 teams
So,
Required number of ways= 8 x 7 x 6
= 336

Correct Option: 4 Best Solution (4)