Ratio and Proportion

(No. of Questions 443) .... SME–242-312

TYPE–I : Questions based on the basic

concept of Ratio & Proportion......SME–247

TYPE–II : Questions based on Fractions

...................................................SME–251

TYPE–III : Questions based on Percentage

...................................................SME–252

TYPE–IV : Questions based on Age

...................................................SME–252

TYPE–V : Questions based on addition,

difference and product ...............SME–254

TYPE–VI : Questions based on L.C.M.

& H.C.F. ......................................SME–256

TYPE–VII : Finding the sum/difference/

product of numbers where some change

has been done in given ratio.......SME–256



Divide Rs.2000 into two shares in the ratio 3:2.


Solutio


3x+2x=200

5x=2000

x=400


3x=1200

2x=800  


A class has 90 students. If the ratio of boys and girls is 7:8, find the number of boys in the class.


Solution:


7x+8x=90

15x=90

x=6


Number of boys=7x=42 




The length and breadth of a rectangle are in the ratio 5:4. Find its perimeter if its area is 180 cm².


Solution:


Let the length and breadth be 5x cm and 4x cm.

5x*4x=180

20x²=180

x²=9

x=3

Length = 15cm

Breadth = 12cm


Perimeter

= 2(l+b)

= 2*27

= 54 cm  



Find the mean proportion between 5 and 45.


Solution:


5:x::x:45


x²=45*5 = 225

x=15




Find the fourth proportion to 3, 7 and 9.


Solution:


3:7::9:x


3x=7*9=63


x=21 



The sum of cubes of two numbers is 280. If the numbers are in the ratio 2:3, find the smallest number.


Solution:


Let the numbers be 2x and 3x.

(2x)³+(3x)³=280

8x³+27x³=280

35x³=280

x³=8

x=2

The numbers are 4 and 6. 


10. Average income of ‘A’ and ‘B’ is

200 and average income of ‘C’

and ‘D’ is 250. The average in-

come of A, B, C and D is

(1) 106.25 (2) 125

(3) 200 (4) 225

(SSC Constable (GD)

Exam, 04.10.2015, Ist Sitting)

11. The average daily income of 7

men, 11 women and 2 boys is

Rs. 257.50. If the average daily

income of the men is Rs.10 more

than that of women and the av-

erage daily income of the women

is Rs.10 more than that of boys,

the average daily income of a man

is

(1) Rs. 277.5 (2) Rs. 250

(3) Rs. 265 (4) Rs. 257

(SSC CGL Tier-II Online

Exam.01.12.2016)

12. The average salary of all the as-

sociates in a team is Rs. 16000.

The average salary of 7 senior

associates is Rs. 24000 and the

average salary of the rest is Rs.

12000. How many associates

work in that team?

(1) 21 (2) 22

(3) 23 (4) 24

(SSC CPO SI, ASI Online

Exam.05.06.2016) (IInd Sitting)

13. The average monthly salary of 19

members of a group is Rs.

16000. If one more member

whose monthly salary is Rs.

20000 joins the group, then the

average salary of the group is

(1) Rs. 18250 (2) Rs. 16200

(3) Rs. 18000 (4) Rs. 16250

(SSC CGL Tier-I (CBE)

Exam. 29.08.2016) (IInd Sitting)

14. The average salary of all workers

in a workshop is Rs.12000. The

average salary of 7 technicians is

Rs.15000 and the average salary

of the rest is Rs. 9000. The total

number of workers in the work-

shop is :

(1) 12 (2) 13

(3) 14 (4) 15

(SSC CGL Tier-I (CBE)

Exam. 04.09.2016 (IInd Sitting)

15. A man spends in 8 months as

much as he earns in 6 months.

He saves Rs. 6000 in a year. His

average monthly income is :

(1) Rs. 2400 (2) Rs. 2000

(3) Rs. 2150 (4) Rs. 1800

(SSC CGL Tier-I (CBE)

Exam. 07.09.2016 (IIIrd Sitting) 


13. Among three numbers, the first

is twice the second and thrice the

third. If the average of the three

numbers is 49.5, then the dif-

ference between the first and the

third number is

(1) 54 (2) 28

(3) 39.5 (4) 41.5

(SSC CGL Tier-1 Exam 26.06.2011

(First Sitting)

14. Out of 4 numbers, whose aver-

age is 60, the first one is one-

fourth of the sum of the last

three. The first number is

(1) 15 (2) 45

(3) 48 (4) 60

(SSC CGL Tier-1 Exam 26.06.2011

(Second Sitting)

15. Of the three numbers, the first

number is twice of the second

and the second is thrice of the

third number. If the average of

these 3 numbers is 20, then the

sum of the largest and smallest

numbers is

(1) 24 (2) 42

(3) 54 (4) 60

(SSC CPO (SI, ASI & Intelligence Officer)

Exam 28.08.2011 (Paper-I)

16. If the arithmetic mean of 3a and

4b is greater than 50, and a is

twice b, then the smallest pos-

sible integer value of a is

(1) 20 (2) 18

(3) 21 (4) 19

(SSC CGL Tier-II Exam. 12.04.2015

TF No. 567 TL 9)

17. Of three numbers, the first is 4

times the second and 3 times the

third. If the average of all the

three numbers is 95, what is the

third number ?

(1) 76 (2) 60

(3) 130 (4) 57

(SSC CGL Tier-II Exam,

2014 12.04.2015 (Kolkata Region)

TF No. 789 TH 7)

18. Among three numbers, second is

twice the first and also thrice the

third. If the average of the three

numbers is 33, then the largest

number is :

(1) 36 (2) 54

(3) 62 (4) 72

(SSC CGL Tier-I (CBE)

Exam. 06.09.2016 (IInd Sitting)