1. A is three times as old as B. C was twice-as old as A four years ago. In four years' time, A will be 31. What are the present ages of B and C ?
a) 9, 46
b) 9, 50
c) 10, 46
d) 10, 50
Explanation: We have : A = 3B ...(i) and
C - 4 = 2 (A - 4) ...(ii)
Also, A + 4 = 31 or A= 31-4 = 27.
Putting A = 27 in (i), we get: B = 9.
Putting A = 27 in (ii), we get C = 50.
2. Today is Varun's birthday. One year, from today he will be twice as old as he was 12 years ago. How old is Varun today ?
a) 20 years
b) 22 years
c) 25 years
d) 27 years
Explanation:Let Varan's age today = x years.
Then, Varan's age after 1 year = (x + 1) years.
Therefore x + 1 = 2 (x - 12) ⇔ x + 1 = 2x - 24 ⇔ x = 25.
3. A bird shooter was asked how many birds he had in the bag. He replied that there were all sparrows but six, all pigeons but six, and all ducks but six. How many birds he had in the bag in all?
a) 9
b) 18
c) 27
d) 36
Explanation: There were all sparrows but six' means that six birds were not sparrows but only pigeons and ducks.
Similarly, number of sparrows + number of ducks = 6 and number of sparrows + number of pigeons = 6.
This is possible when there are 3 sparrows, 3 pigeons and 3 ducks i.e. 9 birds in all.
4. Mr. Johnson was to earn £ 300 and a free holiday for seven weeks' work. He worked for only 4 weeks and earned £ 30 and a free holiday. What was the value of the holiday?
a) £ 300
b) £ 330
c) £ 360
d) £ 420
Explanation:
5. What is the smallest number of ducks that could swim in this formation - two ducks in front of a duck, two ducks behind a duck and a duck between two ducks ?
a) 3
b) 5
c) 7
d) 9
Explanation: Clearly, the smallest such number is 3.
Three ducks can be arranged as shown above to satisfy all the three given conditions.
6. A fires 5 shots to B's 3 but A kills only once in 3 shots while B kills once in 2 shots. When B has missed 27 times, A has killed
a) 30 birds
b) 60 birds
c) 72 birds
d) 90 birds
Explanation:
7. In a class, 3/5 of the students are girls and rest are boys. If 2/9 of the girls and 1/4 of the boys are absent, what part of the total number of students is present ?
a) 17/25
b) 18/49
c) 23/30
d) 23/36
Explanation:
8. In a family, a couple has a son and a daughter. The age of the father is three times that of his daughter and the age of the son is half of that of his mother. The wife is 9 years younger to her husband and the brother is seven years older than his sister. What is the age of the mother ?
a) 40 years
b) 45 years
c) 50 years
d) 60 years
Explanation: Let the daughter's age be x years.
Then, father's age = (3x) years.
Mother's age = (3x - 9) years; Son's age = (x + 7) years.
So, x + 7 = (3x-9)/2 ⇔ 2x + 14 = 3x - 9 ⇔ x = 23.
Therefore Mother's age = (3X - 9) = (69 - 9) years = 60 years.
9. If a 1 mm thick paper is folded so that the area is halved at every fold, then what would be the thickness of the pile after 50 folds ?
a) 100 km
b) 1000 km
c) 1 million km
d) 1 billion km
Explanation:
10. First bunch of bananas has (1/4) again as many bananas as a second bunch. If the second bunch has 3 bananas less than the first bunch, then the number of bananas in the first bunch is
a) 9
b) 10
c) 12
d) 15
Explanation:
