Wednesday, May 1, 2013

Maths Keys of Postal Asst Exam Aprl 21,2013

01. Tarun travels a
distance of 24km at 6
km/hr another distance
of 24km at 8 km/hr and
a third distance of 24
km at 12 km/hr. His
average speed for the
whole journey (in km/
hr) is
(A) 8 2/3
(B) 8
(C) 9
(D) 7
Ans. (B) 8
02. Rohan lends 1000 in
four parts. If he gets
8% interest on 2000, 7
1/2% on 4000 and 8
1/2% on 1400 what
percent of interest
must he get for the
remainder if his
average annual interest
is 8.13%?
(A) 10%
(B) 9%
(C) 8%
(D) None of these
Ans. (B) 9%
03. A solid piece of iron
is in the form of a
cuboid of dimensions
(49cmx33cmx24cm) is
melted and moulded to
form a solid sphere. The
radius of the sphere is
(A) 23 cm
(B) 21 cm
(C) 19cm
(D) 25cm
Ans. (B) 21 cm
04. Twelve solid spheres
of the same size are
made by melting a solid
metallic cylinder of
base diameter 2 cm
and height 16cm. The
diameter of each
sphere is:
(A) 4cm
(B) 3cm
(C) 2 cm
(D) 6 cm
Ans. (C) 2 cm
05. Perimeter of a circle
is equal to the
perimeter of a square
whose area is 484 cm².
What is the radius of
the circle?
(A) 14cm
(B) 12 cm
(C) 7 cm
(D) 16 cm
Ans. (A) 14cm
06. Puneeta borrowed
from Reena certain
sum for two years at
simple interest.
Puneeta lent this sum
to Venu at the same
rate for two years
compound interest. At
the end of two years
she received 110 as
compound interest but
paid 100 as simple
interest. Find the sum
and rate of interest:
(A) 250, rate 20% per
(B) 250, rate 25% per
(C) 250, rate 10% per
(D) None of these
Ans. (A) 250, rate 20%
per annum
07. 13 chairs and 5
tables were brought for
8280. If the average
cost of the table will be
1227, what is the
average cost of a
(A) 2145
(B) 165
(C) 175
(D) None of these
Ans. (B) 165
08. A man goes uphill
with an average speed
of 24 kmph and comes
down with an average
speed of 36 kmph. The
distance travelled in
both the cases being
the same, The average
speed (in km/hr) for the
entire journey is:
(A) 30.8
(B) 32.8
(C) 28.8
(D) None of these
Ans. (C) 28.8
09. 40% of the
employees of a certain
company are men, and
75% of the men earn
more than 25000 per
year. If 45% of the
company's employees
earn more than 25000
per year, what fraction
of the women employed
by the company earn
25000 per year or less?
(A) 1/4
(B) 3/4
(C) 1/3
(D) 2/11
Ans. (B) 3/4
10. A sum of money
invested at compound
interest amounts in 3
years to 800 and in 4
years to 840 what is
the percentage rate of
(A) 6%
(B) 5%
(C) 4%
(D) 3%
Ans. (B) 5%
11. If the difference
between simple and
compound interest on
some principal amount
at 20% per annum for
three years is 48, then
the principal amount is:
(A) 390
(B) 375
(C) 450
(D) None of these
Ans. (B) 375
12. A rational number
between 1/2 and 3/5 is:
(A) 4/7
(B) 3/5
(C) 2/5
(D) None of these
Ans. (A) 4/7
13. The curved surface
of a cylinder is 264m².
Its volume is 924m³. The
height of the cylinder
must be:
(A) 8 m
(B) 6 m
(C) 4 m
(D) None of these
Ans. (B) 6 m
14. If by selling 110
apples, the cost price
of 120 apples is
realized. The gain % is?
(A) 10 10/11%
(B) 9 1/9%
(C) 11 1/9%
(D) 9 1/11%
Ans. (D) 9 1/11%
15. If 8 men or 12
women can do a piece
of work in 25 days, in
how many days can the
same work be done by
6 men and 11 women?
(A) 15 days
(B) 13 1/2 days
(C) 12 days
(D) 18 days
Ans. (A) 15 days
16. Pujara has a certain
average of runs for his
8 matches in Border
Gavaskar Trophy. In the
ninth match he scores
100 runs and thereby
increases his average
by 9 runs. His new
average of runs is:
(A) 28
(B) 24
(C) 20
(D) 32
Ans. (A) 28
17. It costs 1 to
photocopy a sheet of
paper. However, 2%
discount is allowed on all
photocopies done after
first 1000 sheets. How
much will it cost to
photocopy 5000 sheets
of paper?
(A) 3920
(B) 4900
(C) 4920
(D) 3980
Ans. (C) 4920
43 & 44) Answer the
following questions on
the basis of the
information given below.
i. Trains A and B are
travelling on the same
route heading towards
the same destination.
Train B has already
covered a distance of
220km before the train
A started.
ii. The two trains meet
each other after 11
hours after start of
train A
iii. Had the trains been
travelling towards each
other (from a distance
of 220 km) they would
have met after one
18. What is the speed of
trains 'B' in kmph:
(A) 116
(B) 180
(C) 100
(D) None of these
Ans. (C) 100
19. What is the speed of
trains 'A' in kmph:
(A) 118
(B) 80.5
(C) 102
(D) None of these
Ans. (D)
approximate (you are
not expected to
calculate the exact
value) value will come in
place of the question
mark(?) in following
20. 384.996 x 15.001 +
44.99 = ?
(A) 5080
(B) 5820
(C) 5280
(D) 5420
Ans. (B) 5820
21. Three men or eight
boys can do a piece of
work in 17 days. How
many days will two men
and six boys together
take to finish the same
(A) 12 days
(B) 17 days
(C) 11 days
(D) None of these
Ans. (A) 12 days
22. Vaibhav got a
monthly increment of
12 percent of Pushpa's
monthly salary.
Pushpa's monthly
salary is 7800. Vaibhav's
monthly salary before
increment was 6500.
What amount will he
earn in five months
after his increment?
(A) 37.180
(B) 35.180
(C) 36.180
(D) None of these
Ans. (A) 37.180
23. The ratio of two
numbers is 4:5. When
the first is increased by
20% and the second is
decreased by 20% the
ratio of the resulting
numbers is:
(A) 5:6
(B) 5:4
(C) 6:5
(D) 4:5
Ans. (C) 6:5
24. If the numerator of
a fraction be increased
by 12% and its
denominator decreased
by 2% the value of the
fraction becomes 6/7.
Thus, the original
fraction is:
(A) 3/4
(B) 4/3
(C) 2/3
(D) None of these
Ans. (A) 3/4
25. What approximate
value will come in place
of the question mark
(?) in the following
239.99 / 8.0001 x 9.99
= ?
(A) 350
(B) 260
(C) 400
(D) 300
Ans. (D) 300