M4maths Previous Puzzles

07 Jun 2012 profit loss

In a business a man found a loss of 27% in a particular year. Then he decided to invest the remaining amount in a second business for the next year. What profit he should get in the second business in the second year to make a condition of no profit no loss in the end of second year.
Give answer in approx

OPtion

1) 27
2) 30
3) 34
4) 37
5) 43
6) 44
7) 45
8) 47
9) 48
10) none of these

Solution

let the initial investment = 100
so after first year of loss remaining amount = 100-27 = 73
let the profit factor (profit percent/100) = x
so according to the given condition
73(1+x) = 100
or 1+x = 100/73
or x = 100/73 - 1 = 27/73 = 0.3699
means 36.99 = 37 %

Correct Option: 4 Best Solution (0)

06 Jun 2012 sequence

7, 19, 37, 61, ?

OPtion

1) 91
2) 93
3) 97
4) 103
5) 105
6) 123
7) 125
8) 129
9) 131
10)none of these

Solution

2^3-1^3 = 8-1 = 7
3^3-2^3 = 27-8 = 19
4^3-3^3 = 64-27 = 37
5^3-4^3 = 125-64 = 61
6^3-5^3 = 216-125 = 91

Correct Option: 1 Best Solution (0)

05 Jun 2012 cost

cost of 3 toys A, B and C are 50, 90 and 120 rupee respectively.
There are 3 free schemes for shopkeepers by their dealer.

1) buy 5 A and 10 B get 2 C free
2) buy 4 B and 8 C get 4 A free
3) buy 6 C and 12 A get 3 B free

Which scheme is most profitable for a shopkeeper

OPtion

1) first
2) second
3) third
4) first and second are equally likely
5) second and third re equally likely
6) third and first are equally likely
7) all are equally likely

Solution

in first scheme total investment = 5*50+10*90 = 1150
and free toys cost = 120*2 = 240
so profit investment ratio = 240/1150 = 0.2087
similarly in second scheme investment = 1320 and free toys cost = 200
so profit investment ratio = 200/1320 = 0.1515
and in third case investment = 1320 and profit = 270
so profit investment ratio = 270/1320 = 0.2045
so first scheme is best for a shopkeeper

Correct Option: 1 Best Solution (0)

04 Jun 2012 MONDAY

rank of the word MONDAY in the dictionary of all words formed by using the letters of the word MONDAY.

OPtion

1) 320
2) 321
3) 322
4) 323
5) 324
6) 325
7) 326
8) 327
9) 328
10) none of these

Solution

total words = 6*5*4*3*2*1 = 720
so rank of MONDAY
= [720/6]*2+[120/5]*3+[24/4]*2+[6/3]*1+[2/2]*0+1 = 240+72+12+2+0+1 = 327

Correct Option: 8 Best Solution (0)

01 Jun 2012 sum the series

sum the series
1+1.1+1.21+1.331+1.4641+................. upto infinite terms

OPtion

1) 12342.9991
2) 13429.8845211
3) 34294598.65454111
4) 123.124352111
5) 49559.234111
6) 19.495111
7) 5496385.1111
8) 112321.1232111
9) infinite
10) none of these

Solution

since common ratio of the given GP is 1.1>1 so sum will be infinite

Correct Option: 9 Best Solution (0)

31 May 2012 solve

[(2^12)(3^8)(6^10)]^1/9
The valve of the given expression lies between

OPtion

1) 4 to 9
2) 9 to 18
3) 1 to 36
4) 5 to 35
5) 36 to 72
6) 25 to 36
7) 72 to 144
8) 81 to 100
9) 100 to 110
10) none of these

Solution

[(2^12)(3^8)(6^10)]^1/9
= [2^(12+10) * 3^(8+10)]^1/9
= [2^22 * 3^18]^1/9
= [2^2 * 3^2] * 2^(4/9)
= 36 * 2^(4/9)
= 36 * (a number between 1 and 2)

Correct Option: 5 Best Solution (0)

30 May 2012 sum

The sum of a number of two digits and the number obtained by exchanging the places of digits is 110. If units place is 4 more than the tens place in the given number, then product of two digits of the number will be

OPtion

1) 64
2) 46
3) 37
4) 73
5) 19
6) 91
7) 82
8) 28
9) 21
10) none of these

Solution

Let the number is 10x+y so second number will be 10y+x
so sum will be 11x+11y = 110 so x+y = 10 and y-x = 4
so 2y = 14 so y = 7 and x = 3

Correct Option: 9 Best Solution (9)

29 May 2012 sequence?)

fill the blank space
96,45,16,3,0,?

OPtion

1) -4
2) -7
3) -10
4) -24
5) -1
6) 1
7) 4
8) 8
9) 10
10) none of these

Solution

5^3-5^2-5+1 = 96
4^3-4^2-4+1 = 45
3^3-3^2-3+1 = 16
2^3-2^2-2+1 = 3
1^3-1^2-1+1 = 0
0^3-0^2-0+1 = 1

Correct Option: 6 Best Solution (0)

28 May 2012 solve

if x+(1/x)=4 then x = ?

OPtion

1) 2+sqrt(2)
2) 2+sqrt(3)
3) 3+sqrt(5)
4) 3+sqrt(2)
5) 5+sqrt(3)
6) 5+sqrt(2)
7) 4+sqrt(3)
8) 4+sqrt(2)
9) 2+sqrt(5)
10) none of these

Solution

x+(1/x)=4
so x-(1/x)=sqrt[{x+(1/x)}^2 - 4]
=sqrt(12) = 2sqrt(3)
on adding these 2 eq. we get x = 2+sqrt(3)

Correct Option: 2 Best Solution (16)

25 May 2012 Amount

Amount obtained after 3 year in a principle of 90000 rupee by taking interest rate as 10 % yearly will be

OPtion

1) 119790
2) 115680
3) 112370
4) 111190
5) 104590
6) 108980
7) 110980
8) 117690
9) 115690
10) none of these

Solution

according to the given condition
amount = 90000*1.1*1.1*1.1 = 119790

Correct Option: 1 Best Solution (0)