Quantitative Ability (Part 7 of 9)

The average age of a couple is 25 years. The average age of the family just after the birth of the first child was 18 years. The average age of the family just after the second child was born was 15 years. The average age of the family after the third and the fourth children (who are twins) were born was 12 years. If the present average age of the family of six persons is 16 years, how old is the eldest child?

6 years

7 years

8 years

9 years
Answer: d


10% of the voters did not cast their vote in an election between two candidates. 10% of the votes polled were found invalid. The successful candidate got 54% of the valid votes and won by a majority of 1620 votes. The number of voters enrolled on the voters list was:

25000

33000

35000

40000
Answer: a


The resistance of a wire is proportional to its length and inversely proportional to the square of its radius. Two wires of the same material have the same resistance and their radii are in the ratio 9: 8. Lf the length of the first wire is 162 cms. find the length of the other.

64cm.

120cm.

128 em.

132cm.
Answer: c


If f (x + y/8, xy/8) = xy, then f (m, n) + f (n, m) = 0

only when m = n

only when m? n

only when m = n

for all m and n
Answer: d


A person closes his account in an investment scheme by withdrawing Rs. 10, 000. One year ago he had withdrawnRs. 6000. Two years ago he had withdrawn Rs. 5000 Three years ago he had not withdrawn any money. How much money had he deposited approximately at the time of opening the account 4 years ago, if the annual simple interest is 10%?

Rs. 15600

Rs. 16500

Rs. 17280

None of these
Answer: a


It takes 6 technicians a total of 10 hours to build a new server from direct computer, with each working at the same rate. If six technicians start to build the server at 11: 00 am, and one technician per hour is added beginning at 5: 00 pm, at what time will the server be completed?

6: 40pm

7: 00pm

7: 20pm

8: 00pm
Answer: d


A ship 55 kms. From the shore springs a leak which admits 2 tones of water in 6 min; 80 tones would suffer to sink her, but the pumps can throw out 12 tones an hour. Find the average rate of sailing that she may just reach the shore as she begins to sink.

5.5km/h

6.5km/h

7.5km/h

8.5km/h
Answer: a


In a 400 meter race around a circular stadium having a circumference of 1000 meters, the fastest runner and the slowest runner reach the same point at the end of the 5th minute, for the first time after the start of the race. All the runners have the same starting point and each runner maintains a uniform speed throughout the race. If the fastest runner runs at twice the speed of the slowest runner, what is the time taken by the fastest runner to finish the race?

20mins

15mins

10mins

5mins
Answer: c


A train crosses a platform 100 metres long in 60 seconds at a speed of 45 km per hour. The time taken by the train to cross an electric pole, is

8 seconds

1 minute

52 seconds

Data inadequate
Answer: c


Two vertical lampposts of equal height stand oneither side of a road 50m wide. At a point P on the road between them, the elevation of the tops of the lampposts are 60° and 30° Find the distance of P from the lamp post which makes angle of 60°

25m

12.5m

16.5m

20.5m
Answer: b


There are three coplanar parallel lines. If any p points are taken on each ofthe lines, then find the maximum number of triangles with the vertices of these points.

p2 (4p − 3)

p3 (4p − 3)

p (4p − 3)

p3
Answer: a
