1. If the radius of a circle is increased by 50%, its area is increased by
a) 125%
b) 100%
c) 75%
d) 50%
e) None of these
2. A and B together can do a work in 10 days. B and C together can do the same work in 6 days. A and C together can do the work in 12 days. Then A, B and C together can do the work in?
a) 28 days
b) 14 days
c) 40/7 days
d) 58/ 7 days
e) None of these
3. A bicycle wheel makes 5000 revolution in moving 11 km. The diameter of the wheel, in cm, is
a) 35
b) 55
c) 65
d) 70
e) None of these
4. Water is flowing at the rate of 3km/hr through a circular pipe of 20 cm internal diameter into a circular cistern of diameter 10m and depth 2 m. In how much time will the cistern be filled?
a) 1 hr
b) 1 hr 40 min
c) 1 hr 20 min
d) 2 hr s 40 min
e) None of these
5. The single discount equal to three consecutive discounts of 10%, 12% and 5% is
a) 26.27%
b) 24.76%
c) 9%
d) 11%
e) None of these
6. An article is marked 40% above the cost price and discount of 30% is allowed. What is the gain or loss percentage?
a) 10 % gain
b) 5% gain
c) 2% loss
d) 12% loss
e) None of these
7. The average age of 11 players of a cricket team is increased by 2 months when two of them aged 18 years and 20 years are replaced by two new players. The average age of the new players is
a) 19 years 1 month
b) 19 years 6 month
c) 19 years 11 month
d) 19 years 5 month
e) None of these
8. From a point P on a level ground, the angle of elevation of the top tower is 30º. If the tower is 100 m high, the distance of point P from the foot of the tower is:
a) 100v3
b) 100/ v3
c) 200v3
d) 200/v3
e) None of these
9. Walking at 5 km/hr a student reaches his school from his house 15 minutes early and walking at 3 km/hr he is late by 9 minutes. What is the distance between his school and his house?
a) 5 km
b) 8 km
c) 3 km
d) 2 km
e) None of these
10. In a town, 80% of the population are adults of which the men and women are in the ratio of 9 : 7, respectively. If the number of adult women is 4.2 lakh, what is the total population of the town?
a) 12 lakh
b) 9.6 lakh
c) 9.8 lakh
d) 11.6 lakh
e) None of these
Answers:
SOLUTION Q1:
If radius of a circle = 100, then area of a circle = R2
Net it is increasing from 100 to 225 so there will be overall 125% increase.
SOLUTION Q2:
A and B together can do a work in 10 days.
B and C together can do the same work in 6 days.
A and C together can do the work in 12 days.
Let total work done = LCM of 10, 6 & 12 = 60 units
(A + B)’ s 1 day work = 60/ 10 = 6 units
(B + C)’ s 1 day work = 60 / 6 = 10 units
(C + A)’ s 1 day work = 60/ 12 = 5 units
Adding these three questions (2A + 2B + 2C)’s 1 day work = 21 units
(A + B + C)’s 1 day work = 21/2 units
So A + B + C will do whole work = 60 / (21/2) = 120/21 = 40/7 days
SOLUTION Q3:
A bicycle wheel makes 5000 revolution in 11km.
We know in 1 revolution, a wheel cover a circumference = 2R
So in 5000 revolution it will cover = 2R×5000 =
11km = 11000m = 11,00,000 cm
Hence R = 35 cm
Hence diameter = 70 cm
SOLUTION Q4:
Water is flowing at the rate of 3kmph through a circular pipe of 20 cm = 0.2 cm , internal diameter
So volume of water flows through pipe in an
hour = × 0.12×3000 m3 = 30
Volume of cistern = ×52×2 = 50
So time taken by pipe to fill cistern = Volume of cistern/ volume filled by pipe in an hour
= 50 /30 = 5/3 hr = 1hr 40 min
SOLUTION Q5:
100 90
100 88
100 95
net 100000 75240
100 75.24 so single discount = 100 – 75.24
= 24.76%
SOLUTION Q6:
Let cost price be 100 the marked price = 140 then discount = 140 ×0.7 = 98
So there is net 2% loss.
SOLUTION Q7:
Two players of age 18 yr & 20 yr is replaced i.e. total 38 year age is replaced. Total average age is increased by 2 months & so total age increased of two men is 11× 2 =
22 months. So now total of both person = 38 yr 22 months
Hence their average = 19 yr 11 months
SOLUTION Q8:
Let AB be the tower.
Then, APB = 30º and AB = 100 m
The ratio of sides opposite to angle of 30 – 60 – 90 is
1 :v3 : 2
So if side opposite to angle of 30o is 100 & side opposite to angle of 60o is 100v3.
SOLUTION Q9:
Distance travelled by him = =
== 3km
SOLUTION Q10:
12 lakh--- let the number of adult men be x.
Then, ratio of the numbers of adult men and adult women
9 : 7 = x : 4.2
=> x = 9/7 * 4.2 = 5.4 lakh
Total adult population = 4.2 + 5.4 = 9.6 lakh
If the population of the town be y lakh, then 80y/100 = 9.6
=> y = (9.6*100)/80 = 12 lakh.
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