M4maths Previous Puzzles

16 Sep 2010 3 number in sequence

There are 4 numbers in a sequence in such a way that first 3 numbers have a common difference and
last 3 have a common ratio. If middle 2 numbers are 5 and 10 then product of first and last number is

OPtion

1) 50
2) 8
3) 24
4) 30
5) 40
6) 12
7) 28
8) 16
9) 18
10) 0

Solution

Let first number is x, then according to first given condition
5-x = 10-5, hence x = 0
Similarly let last number is y, then 10/5 = y/10, hence y = 20

Correct Option: 10 Best Solution (0)

15 Sep 2010 find difference

The sum of a number and its reciprocal is 2 what will be the difference of this number and its reciprocal ?

OPtion

1) 1
2) 2
3) 3
4) 4
5) 5
6) 6
7) 7
8) 8
9) 9
10) 0

Solution

let the numebr is x

x + 1/x = 2
x^2 - 2x + 1 = 0
By solve the equation
x=1
so 1/x = 1
Then 1-1/1= 1-1 = 0

Correct Option: 10 Best Solution (18)

14 Sep 2010 what will be the next number

what will be the next
5, 8, 12, 18, 24, 30, ?

OPtion

1) 41
2) 37
3) 38
4) 35
5) 39
6) 40
7) 36
8) 42
9) 43
10) 44

Solution

2, 3, 5, 7, 11, 13, 17, 19
5, 8, 12, 18, 24, 30, 36

Correct Option: 7 Best Solution (14)

13 Sep 2010 find the number

A nonzero number is such that nine times of it is equal to the square of its 75 percent, the number is?

OPtion

1) 16
2) 4
3) 8
4) 10
5) 9
6) 6
7) 7.5
8) 12
9) 15
10) 1

Solution

Answer: 9 x = (.75 x)2
Hence x = 16

Correct Option: 1 Best Solution (8)

10 Sep 2010 number product

The sum of six successive integers is 39. Their product will be

OPtion

1) 38670
2) 48790
3) 32650
4) 44680
5) 60480
6) 67850
7) 42790
8) 65480
9) 54680
10) 52150

Solution

x + (x+1) + (x+2) + (x+3) + (x+4) + (x+5) = 39
Implies that 6x + 15 = 39
Implies that 6x = 24
Implies that x = 4

Correct Option: 5 Best Solution (0)

09 Sep 2010 investment and loss

A man earns 40 % profit in his investment of 1000000 rupee, after then he invests all the money in a second business,
in which he losses 30 % of the investment. What % of the initial investment he losses.

OPtion

1) 6
2) 1
3) 4
4) 2
5) 5
6) 3
7) 4.5
8) 3.5
9) 10/7
10) 20/7

Solution

After first business total amount received = 1000000 * 140 /100 = 1400000
After second business total amount received = 1400000 * 70 /100
= 980000
Loss = 20000
% loss = 20000 *100 / 1000000
= 2

Correct Option: 4 Best Solution (8)

08 Sep 2010 find the number?

The sum of a number, its fifth part and fifth part of its fifth part is 310. Number is?

OPtion

1) 290
2) 270
3) 235
4) 185
5) 125
6) 230
7) 340
8) 540
9) 250
10) 190

Solution

x + (x/5) + (x/5)/5 = 310
31x/25 = 310
x = 250

Correct Option: 9 Best Solution (12)

07 Sep 2010 3 friend age

There are six friends. The sum of the ages of all the friends is 126. If the sum of the ages of
elder 3 friends is 5/4 times that of the younger 3, then sum of the ages of younger 3 is

OPtion

1) 90
2) 58
3) 70
4) 75
5) 60
6) 56
7) 49
8) 54
9) 86
10) 80

Solution

Answer: Let the sum of the ages of younger 3 friends is x and that of elder 3 friends is 5/4x.
According to given condition
(5/4) x + x = 126
(9/4) x = 126
x = 126 *4 /9 = 56

Correct Option: 6 Best Solution (3)

06 Sep 2010 Find the number

3, 14, 39, 84, ?

OPtion

1) 125
2) 150
3) 155
4) 200
5) 250
6) 225
7) 175
8) 225
9) 300
10) 165

Solution

1 2 3 4 5 6 7 8 9
1 4 9 16 25 36 49 64 81
1 8 27 64 125 216 343 512 729


3 14 39 84 155 258 399 584 819

Correct Option: 3 Best Solution (11)

03 Sep 2010 Find the next

7, 14, 55, 110, ?

OPtion

1) 220
2) 121
3) 111
4) 221
5) 540
6) 190
7) 185
8) 310
9) 131
10) 200

Solution

add the number and its reverse you will get the next number.
7 + 7 = 14
14+41 = 55
55+55 = 110
110+011 = 121

Correct Option: 2 Best Solution (13)