M4maths Previous Puzzles

14 Mar 2018 Work & Time

If 6 men and 9 women can do a piece of work in 7 days and 5 men and 11 women can do it in 7 days, how

many days will 15 men and 12 women take to do it?

OPtion

1) 3.5
2) 4.75
3) 3.25
4) 3.0
5) 3.75
6) 4.0
7) 4.25
8) 4.5
9) 3.33
10) None of these

Solution

Let a man's daily work is x units and that of a woman is y units.
So total amount of work, W = 7(6x + 9y) = 7(5x + 11y)

Solving we get, 42x - 35x = 77y - 63y
=> 7x = 14 y
=> y/x = 1/2 or y = (1/2)x

Now, 6 x + 9 y can do work in 7 days.
So, 6x + 4.5 x can do work in 7 days.
So, 10.5 x can do work in 7 days.

Now, 15x + 12y = 15x + 6x = 21x

Hence, if 10.5 x can do work in 7 days, 21x can do work in (10.5*7)/18 = 3.5 days.

Correct Option: 1 Best Solution (0)

13 Mar 2018 LCM HCF

The L.C.M of two numbers is 156 and their H.C.F is 2. If the sum of the numbers is 38, then their difference is

OPtion

1) 10
2) 8
3) 9
4) 12
5) 11
6) 14
7) 13
8) 15
9) 16
10) None of these

Solution

Let the numbers be x and (38-x).
Then,
x*(38-x) = 156*2
=> x^2 - 38x + 26*12 = 0
=> x^2 - 26x - 12x + 26*12 = 0
=> x (x-26) -12(x-26) = 0
=> (x-12)(x-26) = 0
The numbers are 12 and 26
Required difference = (26-12) = 14

Correct Option: 6 Best Solution (0)

12 Mar 2018 Series

Find the seventh term of following series:
122, 243, 365, 487, 6011, ....

OPtion

1) 6713
2) 6717
3) 7017
4) 7213
5) 8413
6) 8213
7) 7217
8) 8417
9) 8617
10) None of these

Solution

n term of Series is formed by concatenation of nth tern in 12 table and nth prime number.
So seventh term is: [7*12][17]
=8417

Correct Option: 8 Best Solution (0)

09 Mar 2018 Discount

A trader keeps the marked price of an item 75% above its cost price. The percentage of discount allowed to gain 55% is

OPtion

1) 12.43
2) 11.43
3) 11.13
4) 12.13
5) 11.55
6) 12.55
7) 11.63
8) 12.63
9) 12.75
10) None of these

Solution

Let the CP be 100
then MP = 175
Final SP with Discount = 155

Discount % = (20/175)*100 = 11.43%

Correct Option: 2 Best Solution (0)

08 Mar 2018 Length of Wire

352 cubic centimeters of silver is drawn into a wire 2 mm in diameter. The length of the wire will be:

OPtion

1) 11200 mm
2) 5600 cm
3) 224000 cm
4) 24000 mm
5) 28 m
6) 280 cm
7) 2800 mm
8) 1120 cm
9) 112 m
10) None of these

Solution

Radius in cm = (1/2)*(2/10) = 0.1 cm

Volume of Cylinder = Pi*r^2*l

So, Length l = 352/(Pi*r^2)
=> 352/(22/7 * 0.1 * 0.1)
=> 11200 cm = 112 m

Correct Option: 9 Best Solution (0)

07 Mar 2018 Direction

Rustam started from his house towards north. After covering a distance of 13 km. he turned towards left and covered a distance of 9 km. Then he turns right and covers a distance of 8 and then again he turns left and covers a distance of 2 kms and stops . What is the shortest distance now from his house?

OPtion

1) 23.91
2) 23.17
3) 23.61
4) 21.29
5) 21.31
6) 23.71
7) 22.23
8) 22.81
9) 22.18
10) None of these

Solution

F____
2 |8
|_____
9 |
|13
|
H

Total veritcal distance from house = 13+8 = 21
Total horizontal distance = 11

Shortest distance = sqrt (21^2 + 11^2) = 23.71 KMs

Correct Option: 6 Best Solution (0)

06 Mar 2018 Simple Interest

A person borrows Rs. 37500 for 4 years at 5.75% p.a. simple interest. He immediately lends it to another person at 9.25 p.a for 4 years. Find his gain in the transaction per year.

OPtion

1) 1312.5
2) 1213.5
3) 1413.5
4) 5250
5) 5350
6) 5150
7) 2625
8) 2525
9) 2725
10)None of these

Solution

SI on borrowing = 37500*4*5.75/100 = 8625


SI on Lending = 37500*4*9.25/100 = 13875


Gain per year = (13875 - 8625)/4 = 5250/4 = 1312.5

Option 1)

Correct Option: 1 Best Solution (0)

05 Mar 2018 Probability

In a certain corporation, there are 180 male employees and 90 female employees.  It is known that 20% of the male employees have advanced degrees and 40% of the females have advanced degrees.  If one of the employees is chosen at random, what is the probability this employee doesn't has an advanced degree and is male?

OPtion

1) .043
2) .053
3) .033
4) .133
5) .267
6) 4/15
7) 2/15
8) 8/15
9) 6/15
10) None of these

Solution

Total number of employees = 90+180 = 270

Number of male employess = 180
Number of male employees without advance degree = 80*180/100 = 144

Probability = 144/270 = 48/90 = 16/30 = 8/15

Correct Option: 8 Best Solution (0)

02 Mar 2018 Probability

An alphanumeric character is randomly selected from following sentence:
"Holi is also known as the festival of colours."

What is the probability that its an vowel?
Note: Alphanumeric character means alphabet or number. Space and other characters should be ignored.

OPtion

1) 13/37
2) 13/36
3) 13/35
4) 15/37
5) 15/38
6) 15/34
7) 14/37
8) 12/39
9) 11/35
10) None of these

Solution

Sentence = Holi is also known as the festival of colours..

Total number of alphanumeric character in the sentence = 37
Total Number of vowels = 15 (OIIAOOAEEIAOOOU)

Probability = 15/37

Correct Option: 4 Best Solution (0)

01 Mar 2018 Work & Time

Sweet Makers are needed to prepare Ladoos for Holi celebration. Each Sweet Maker can make either 27 large ladoos per hour, or 127 small ladoos per hour. The kitchen is available for 420 minutes and 756 large ladoos and 6223 small ladoos are needed. How many Sweet Makers are required?

OPtion

1) 15
2) 13
3) 16
4) 12
5) 14
6) 10
7) 17
8) 12.33
9) 10.66
10) None of these

Solution

Lets find out person hours required to prepare the required ladoos for the celebration:
Time taken to cook 756 large ladoos by 1 Sweet Maker = 756/27 =28 hours
Time taken to cook 6223 small ladoos by 1 Sweet Maker = 6223/127= 49 hours
Total hours required by 1 Sweet Maker = 28+49 = 77 hours

As we have kitchen available only for 7 hours, so we need to have more Sweet Makers to finish the work in 7 hours

1 Sweet Maker * 77 hours = X Sweet Maker * 7 hours
So X = 77/7 = 11

Correct Option: 10 Best Solution (0)