M4maths Previous Puzzles

03 May 2019 Stocks

The market value of a 9.5% stock, in which an income of Rs. 999 is derived by investing Rs. 10500, brokerage being 1/4 %, is:

OPtion

1) 99.21
2) 99.84
3) 99.59
4) 99.15
5) 99.16
6) 99.96
7) 99.75
8) 99.46
9) 99.65
10) None of these

Solution

For an income of Rs. 999, investment = Rs. 10500

For an income of Rs. 9.5, investment = Rs. (10500/999) * 9.5 = 99.84
For a Rs. 100 stock, investment = Rs. 99.84

Market value of Rs. 100 stock = Rs. 99.84 - 0.25 = Rs. 99.59

Option 3)

Correct Option: 3 Best Solution (0)

02 May 2019 Factors

How many factors of 534534400 are odd number?

OPtion

1) 12
2) 8
3) 16
4) 18
5) 25
6) 15
7) 30
8) 40
9) 24
10) None of these

Solution

534534400 = 2^8 * 5^2 * 17^4

Any factor of this number should be of the form 3^a * 5^b * 17^c.

For the factor to be a odd number a should be 0

b can take values 0, 1, 2
and c can take values 0, 1, 2, 3, 4

Total number of odd factor = 3 * 5 = 15

Correct Option: 6 Best Solution (2)

01 May 2019 Perfect Squares

How many factors of 105488578125 are perfect squares?

OPtion

1) 20
2) 48
3) 18
4) 60
5) 24
6) 16
7) 36
8) 32
9) 40
10) None of these

Solution

105488578125 = 3^9 * 5^6 * 7^3

Any factor of this number should be of the form 3^a * 5^b * 7^c.

For the factor to be a perfect square a,b,c have to be even.

a can take values 0, 2, 4, 6, 8
b can take values 0, 2, 4, 6
and c can take values 0, 2

Total number of perfect squares = 5 * 4 * 2 = 40

Correct Option: 9 Best Solution (0)

30 Apr 2019 Number

A two digit number is 4 times to its sum of digits. When 18 is added to the number, the digits will get reversed. Then what is that number?

OPtion

1) 36
2) 48
3) 12
4) 42
5) 60
6) 72
7) 18
8) 24
9) 27
10) None of these

Solution

Let the 2 digit number be yx
When 18 is added digits are reversed.
(10x+y)-(10y+x)=18
solving we get x-y=-2
There are so many possibilities of different values of x,y vix
(1,3),(2,4)(3,5),(4,6)(5,7),(6,8),(7,9)
But from the above possibilities, the condition satsfies is the number 24
2+4 = 6
=> 6*4 = 24

Correct Option: 8 Best Solution (5)

29 Apr 2019 Profit & Loss

By selling 48m of cloth, one gains the selling price of 12m. Find the gain percent?

OPtion

1) 33.33%
2) 25%
3) 50%
4) 30%
5) 27.33%
6) 60%
7) 36.66%
8) 24%
9) 27%
10) None of these

Solution

S.P of 48 m=48
S.P of 12 m=12
profit=12
C.P of 48 m = 48 - 12 = 36
(12/36)*100 = 33.33 %

Correct Option: 1 Best Solution (0)

26 Apr 2019 Percentage

A school has 18% students from Maharashtra, out of these 30% are Mumbai students. Find the total percentage of students from Mumbai ?

OPtion

1) 54%
2) 27%
3) 5.0%
4) 4.0%
5) 5.4%
6) 6.0%
7) 8.0%
8) 7.0%
9) 10%
10) None of these

Solution

Total percentage of students from Maharashtra = 18%
Percentage of Mumbai students among 18% of Maharashtra students = 30%
Total percentage of students from Mumbai = 30% of 18 = (30*18)/100 = 5.4%

Option 5)

Correct Option: 5 Best Solution (0)

25 Apr 2019 Time and Distance

Shaktiman saw a criminal at a distance of 75m. When Shaktiman started chasing him the criminal also started running. If the ratio of Speeds of Shaktiman to Criminal is 8:7. Then much distance did Shaktiman run to catch the Criminal?

OPtion

1) 420m
2) 425m
3) 475m
4) 520m
5) 433m
6) 4200m
7) 4215m
8) 4350m
9) 4275m
10) None of these

Solution

Let the distance traveled by criminal before he is caught be x

Time taken by Shaktiman = Time taken by Robber

(75 + x)/8 = x/7
=> x = 525 m
Distance travelled by Shaktiman = 525 + 75 = 600 m

Option 10)

Correct Option: 10 Best Solution (0)

24 Apr 2019 Area

If the diagonal of a rectangle is 18cm long and its perimeter is 44 cm. Find the area of the rectangle.

OPtion

1) 70 sq.cm
2) 76 sq.cm
3) 78 sq.cm
4) 74 sq.cm
5) 75 sq.cm
6) 72 sq.cm
7) 80 sq.cm
8) 86 sq.cm
9) 94 sq.cm
10) None of these

Solution

Let length = x and breadth = y then

2(x+y) = 44 => x+y = 22
x²+y² = 18² = 324
now (x+y)² = 22²
=> x²+y²+2xy= 484
=> 324 + 2xy = 484
=> xy = 80

Area = xy = 80 sq.cm

Correct Option: 7 Best Solution (6)

23 Apr 2019 Series

What is the next term of following series:
1, 2, 4, 6, 10, 12, 16, ?

OPtion

1) 19
2) 18
3) 20
4) 21
5) 23
6) 22
7) 24
8) 25
9) 26
10) None of these

Solution

nth term = n - 1
Where n is prime number such as 2, 3, 5, 7, 11, 13, 17, 19 and so on
So next term = 19 - 1 = 18

Option 2)

Correct Option: 2 Best Solution (0)

22 Apr 2019 Age

The present age of a brother is 7 years more than three times the age of his sister. Nine years hence, brother’s age will be 6 years more than twice the age of the sister. Find the present age of the brother.

OPtion

1) 18
2) 22
3) 30
4) 31
5) 27
6) 24
7) 21
8) 28
9) 32
10) None of these

Solution

Let the sister’s present age be ‘n’ years.
=> brother’s present age = (3n + 7) years
So, according to the question
(3n + 7 + 9) = 2 (n + 9) + 6
=> 3n + 16 = 3n + 24
=> n = 8
Hence, brother’s present age = (3n + 7) = 31 years

Correct Option: 4 Best Solution (5)