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1) A man collects cigarette stubs and makes one full cigarette with every 8 stubs.
If he gets 64 stubs how many full cigarettes can he smoke.

Ans: 8+1=9

2) A soldier looses his way in a thick jungle. At random he walks from his camp but mathematically in an interesting fashion. First he walks one mile East then half mile to North. Then 1/4 mile to West, then 1/8 mile to South and so on making a loop.
Finally how far he is from his camp and in which direction.

Ans: Distance travelled in north and south directions
1/2 – 1/8 + 1/32 – 1/128 + 1/512 – and so on
= 1/2/((1-(-1/4))
Similarly in east and west directions
1- 1/4 + 1/16 – 1/64 + 1/256 – and so on
= 1/(( 1- ( – 1/4))
Add both the answers

3) How can 1000000000 be written as a product of two factors neither of them containing zeros

Ans: 2 power 9 x 5 power 9

4) Conversation between two mathematcians:
First : I have three childern. The product of their ages is 36.
          If you sum their ages, it is exactly same as my neighbour’s door number on my left.
The second mathematician verfies the door number and says that it is not sufficient.
Then the first says ” Ok one more clue is that my youngest is really the youngest”. Immmediately the second mathematician answers .
Can you answer the question asked by the first mathematician?
What are the childeren ages?

Ans 1,6 and 6

5) Light glows for every 13 seconds . How many times did it glow between 1:57:58 and 3:20:47 am.

Ans : 383 + 1 = 384

6) 500 men are arranged in an array of 10 rows and 50 columns according to their heights.
Tallest among each row of all are asked to fall out.
And the shortest among them is A.
Similarly after resuming that to their original podsitions that the shortest among each column are asked to fall out.
And the tallest among them is B .
Now who is taller among A and B ?

Ans A


7) A person with some money spends1/3 for cloths, 1/5 of the remaining for food and 1/4 of the remaining for travel.
He is left with Rs 100/- .
How much did he have with him in the begining ?

Ans: Rs 250/-

8) There are six boxes containing 5 , 7 , 14 , 16 , 18 , 29 balls of either red or blue in colour.
Some boxes contain only red balls and others contain only blue.
One sales man sold one box out of them and then he says
” I have the same number of red balls left out as that of blue “.
Which box is the one he solds out ?

Ans: Total no of balls = 89 and (89-29 /2) = 60/2 = 30
and also 14 + 16 = 5 + 7 + 18 = 30

9) A chain is broken into three pieces of equal lenths containing 3 links each.
It is taken to a backsmith to join into a single continuous one .
How many links are to to be opened to make it ?

Ans : 2.

10) Grass in lawn grows equally thick and in a uniform rate.
It takes 24 days for 70 cows and 60 days for 30 cows to eat the whole of the grass.
How many cows are needed to eat the grass in 96 days.?

Ans : 20
g – grass at the beginning
r – rate at which grass grows, per day
y – rate at which one cow eats grass, per day
n – no of cows to eat the grass in 96 days
g + 24*r = 70 * 24 * y
g + 60*r = 30 * 60 * y
g + 96*r = n * 96 * y
Solving, n = 20.


11. From a vessel, 1/3rd of the liquid evaporates on the first day.
    On the second day 3/4th of the remaining liquid evaporates.
    What fraction of the volume is present at the end of the second day.

Ans: 50%

12. An orange glass has orange juice and white glass has apple juice both of equal volumes.
    50ml of the orange juice is taken and poured into the apple juice.
    50ml from the white glass is poured into the orange glass.
    Of the two quantities, the amount of apple juice in the orange glass and the amount of orange juice in the white glass,      which one is greater and by how much?

Ans: The two quantities are equal

13. There is a 4 inch cube painted on all sides.
    This is cut down into of 1 inch cubes.
    What is the no of cubes which have no pointed sides.

Ans:  8

14. Sam and Mala have a conversation.

  • Sam says I am certainly not over 40
  • Mala says I am 38 and you are atleast 5 years older than me
  • Now Sam says you are atleast 39

All the statements by the two are false.
How old are they really?

Ans: Mala = 38 yrs
        Sam  = 41 yrs. 

15. Ram Singh goes to his office in the city, every day from his suburban house.
    His driver Gangaram drops him at the railway station in the morning and picks him up in the evening.
    Every evening Ram Singh reaches the station at 5 O’ Clock.
    Gangaram also reaches at the same time.
    One day Ram Singh started early from his office and came to the station at 4 O’ Clock.
    Not wanting to wait for the car he starts walking home. Mangaram starts at normal time, picks him up on the way
    and takes him back house, half an hour early.
How much time did Ram Singh walk?

16. In a railway station, there are two trains going.
   One in the harbour line and one in the main line, each having a frequency of 10 minutes.
   The main line service starts at 5 o’clock and the harbour line starts at 5.02A.M.
   A man goes to the station every day to catch the first train that comes.
   What is the probability of the man catching the first train?

Ans: 0.8

17. A family X went for a vacation.
    Unfortunately it rained for 13 days when they were there.
    But whenever it rained in the mornings, they had clear afternoons and vice versa.
    In all they enjoyed 11 mornings and 12 afternoons.
    How many days did they stay there totally?

Ans: 18

18. A survey was taken among 100 people to find their preference of watching T.V. programmes.
    There are 3 channels. Given the no of people who watch

  • at least channel 1
  • at least channel 2
  • at least channel 3
  • no channels at all
  • atleast channels 1and 3
  • atleast channels 1 and 2
  • atleast channels 2 and 3

Find the no of people who watched all three.

19. Albert and Fernandes have two leg swimming race.
      Both start from opposite ends of the pool.
      On the first leg, the boys pass each other at 18 m from the deep end of the pool.
      During the second leg they pass at 10 m from the shallow end of the pool.
      Both go at constant speed but one of them is faster.
      Each boy rests for 4 seconds at the end of the first leg.
     What is the length of the pool?

20. Each alphabet stands for one digit in the following multiplication.

      T H I S
      x     I S
    X F X X
    X X U X

What is the maximum value T can take?

Ans:  T max value = 4




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