# Average Questions for SSC CGL Tier 2 PDF

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## Average Questions for SSC CGL Tier 2 PDF

Download SSC CGL Tier 2 Average Questions PDF. Top 15 SSC CGL Tier 2 Average questions based on asked questions in previous exam papers very important for the SSC exam.

Question 1: The average of odd numbers upto 100 is

a) 50.5

b) 50

c) 49.5

d) 49

Question 2: The average of three consecutive odd numbers is 12 more than one third of the first of these numbers. What is the last of the three numbers?

a) 15

b) 17

c) 19

Question 3: The average of the first nine integral multiples of 3 is

a) 12

b) 15

c) 18

d) 21

Question 4: A cricket player after playing 10 tests scored 100 runs in the 11th test. As a result, the average of his runs is increased by 5. The present average of runs is

a) 45

b) 40

c) 50

d) 55

Question 5: The average of 6 consecutive natural numbers is K. If the next two natural numbers are also included, how much more than K will the average of these 8 numbers be?

a) 3

b) 1

c) 2

d) 1.8

Question 6: The average of 7, 11, 15, x, 14, 21, 25 is 15, then the value of x is

a) 13.3

b) 12

c) 3

d) 14.5

Question 7: The average salary, per head, of all the workers of an institution is 60. The average salary of 12 officers is = 400; the average salary, per head, of the rest is 56. The total number of workers in the institution is

a) 1030

b) 1035

c) 1020

d) 1032

Question 8: The average of 50 numbers is 38. If two numbers, namely 45 and 55 are discarded, the average of the remaining numbers is

a) 37.5

b) 37.9

c) 36.5

d) 37.0

Question 9: Average age of A, B and C is 84 years. When D joins them the average age becomes 80 years. A new person, E, whose age is 4 years more than D, replaces A and the average of B, C, D and E becomes 78 years. What is the age of A ?

a) 50 years

b) 60 years

c) 70 years

d) 80 years

Question 10: The average of 20 numbers is 15 and the average of first five is 12. The average of the rest is

a) 16

b) 15

c) 14

d) 13

Question 11: The average age of Ram and his two children is 17 years and the average age of Ram’s wife and the same children is 16 years. If the age of Ram is 33 years, the age of his wife is (in years):

a) 31

b) 32

c) 35

d) 30

Question 12: The average age of 14 girls and their teacher’s age is 15 years. If the teacher’s age is excluded, the average reduces by 1. What is the teacher’s age?

a) 32 years

b) 30 years

c) 29 years

d) 35 years

Question 13: The average of 50 numbers is 38. If two numbers namely 45 and 55 are discarded, the average of the remaining numbers is :

a) 35

b) 32.5

c) 37.5

d) 36

Question 14: In a family of 5 members, the average age at present is 33 years. The youngest member is 9 years old. The average age of the family just before the birth of the youngest member was

a) 30 years

b) 29 years

c) 25 years

d) 24 years

Question 15: The average marks of 50 students in a class was found to be 64. If the marks of two students were incorrectly entered as 38 and 42 instead of 83 and 24, respectively, then what is the correct average?

a) 61.24

b) 64.54

c) 62.32

d) 61.86

Require sum of 1+3+5+7+9….99
Applying formula for summation of n digits with a as first digit and d is the difference
sum = $\frac{n}{2} (2a + (n-1) d)$
or this formula can be reduced to $\frac{n}{2} \frac{a + l}{2}$hence for calculating avg. it will be
$\frac{a + l}{2}$ (where $l$ is last term)
so $\frac{1 + 99}{2}$ = 50

Let’s say numbers are $a, a+2, a+4$
So avg. will be $\frac{(a+a+2+a+4)}{3} = \frac{a}{3} +12$
Or a = 15
So numbers will be 15, 17, 19

As we know average of numbers which are in A.P. is = $\frac{a+l}{2}$ (where a is first term and l is last term)
Here a=3
and l= 27
Hence average will be 15

let his average of 10 matches = x

total runs in 10 matches = 10x

in 11th match he scored 100 runs, so

total runs after 11th match = 10x + 100

average of 11 matches = (10x+100)/11

after 11th match the average of his runs is increased by 5, so

(10x+100)/11 = x+5

10x+100 = 11x + 55

x = 45

but present average = x+5 = 45+5 = 50

so the answer is option C.

Let the 6 consecutive numbers be a-3,a-2,a-1,a,a+1,a+2

average = $\frac{SumofElements}{NumberofElements}$

It is given that average of 6 consecutive numbers be k and hence

k = $\frac{a-3+a-2+a-1+a+a+1+a+2}{6}$ = $\frac{6a-3}{6}$ = a – $\frac{1}{2}$

now next two numbers (a+3, a+4) are also added

Sum of 8 numbers = a-3+a-2+a-1+a+a+1+a+2+a+3+a+4 = 8a +4

average of 8 numbers = $\frac{8a+4}{8}$ = a + $\frac{1}{2}$ = k + 1

so average of 8 numbers is more than average of 6 numbers by = k+1 – K = 1

we know that average =$\frac {sum of elements}{numberof elements}$

Number of elements =7

Sum of elements = 7+11+15+14+21+25+x = 93+x

=> Average = $\frac {93+x}{7}$

=> 15 = $\frac {93+x}{7}$

=> x = 12

Let the total number of members in the institution be z

average = $\frac{SumofElements}{NumberofElements}$

Average salary of institution = Rs 60

total salary of Institution =Rs 60z

Given that out of z persons , there are 12 officers and there average salary is = Rs 400

and so total salary of 12 officers = 12 x 400 =Rs 4800

So total salary of other (z-12) members =Rs ( 60z – 4800 )…………..(1)

It is given that average salary of (z-12) persons = Rs 56

and hence from here the total salary of (z-12) people = Rs 56(z-12)……….(2)

Equation 1 and 2 are equal

60z – 4800 = 56z – 672

4z = 4128

z = 1032

Average = $\frac{Sum of Elements}{Number of Elements}$

Given that Initially Number of Elements = 50

Initial Average = 38

Sum of Elements = 50 x 38 = 1900

Now as two numbers are discarded, hence number of elements left = 48

Sum of elements after discarding numbers = 1900 – 55 – 45 = 1800

Hence New Average = $\frac{1800}{48}$ = 37.5

avg age of a,b,c = 84

$\frac{A+B+C}{3}$ = 84

A+B+C = 84*3 =252 ……………………(1)

similarly , $\frac{A+B+C+D}{4}$ = 80

A+B+C+D = 80*4 = 320

so using (1)

252 + D = 320

D = 68 i.e, E = 72 (as mentioned in the question)…………….(2)

$\frac{B+C+D+E}{4}$ = 78

B+C+D+E = 78*4 = 312

using (2)

B+C+68+72 =312

B+C = 172 ……………………………(3)

put (3) in (1)

A = 80

Given that average of 20 numbers = 15

using average = $\frac{Sum}{Numberof Elements}$

Sum of all numbers = 20 x 15 = 300

Average of first five numbers = 12

So sum of first five numbers = 12×5 = 60

Sum of numbers left = 300 – 60 = 240

Number of numbers left = 20 – 5 = 15

So average of left numbers = $\frac{240}{15}$ = 16

let the present age of Ram , Ram’s wife ,and his two children be R ,W,S1,S2 respectively

Average =$\frac{SumofAges}{Number of Ages}$

Given that average age of Ram and his childrens is =17 years

R+S1+S2= 17 × 3 = 51

Given R = 33 years .So, S2+S2 = 51-33 = 18 years

Now given that average age of Rams wife and two children = 16 years

So ,

W+S2+S1= 16×3=48

W= 48-18 =30 years

the average age of 14 girls and teacher is given as 15 and as we know

Average = $\frac {sum of ages}{number ofpersons}$

Sum of ages of girls and teachers = 15×15 =225 years

Now the age of teacher is excluded and as a result the average reduced by 1 .So

New average = 14

New number of persons = 14

Hence new sum of ages after exclusion of teacher = 14x 14 = 196

Hence age of teacher =225-196 = 29 years

Given that average age of 50 members = 38 years

So using , average = $\frac{SumofAge}{number of persons}$

Sum of ages = 50 x 38 = 1900

Now 45 and 55 are discarded and hence number of term left = 48

and Total Sum left = 1900 – 45 – 55 = 1800

New Average = $\frac{1800}{48}$ = 37.5

average age of 5 members = 33×5 = 165 years

given that youngest member has age = 9 years

so 9 years ago , youngest member was not present and for other 4 people, 9 years will be reduced from each person’ age and hence

total age of 4 members apart from the youngest one 9 years ago = 165- 9 – 36 = 120 years

average age when the youngest member was born = $\frac{120}{4}$

= 30 years

Given,A

Average of 50 students in a class = 64

Marks of two members were wrongly copied as 38 and 42 instead of 83 and 24.

Mean = $\frac{\text{Sum of all observations}}{\text{Number of Observations}}$

let the sum of all observations be x

According to the problem,

64 = $\frac{x}{50}$

$64×50$ = $x$

$x$ = 3200

Subtract the wrongly copied numbers from the total sum

= $3200 – (38+42)$

= $3200 – 80$

= $3120$

Now add the new numbers to the total sum

= $3120 + (83+24)$

= 3227

Thus, new sum is 3227

New Mean = $\frac{3227}{50}$ = 64.54

Therefore, new Mean = 64.54

We hope this Average Questions pdf for SSC CGL Tier 2 exam will be highly useful for your Preparation.