Average Questions and Answers for SBI Clerk Pre 2019 and IBPS Clerk Pre 2019 | Daily Quiz 10

Direction : Study the following question carefully and choose the right answer.
1
There are 14 people in a family and the average age of all the family members is 30 years. A new baby born in a family, After 4 years what will be the average age of the all family members?
» Explain it
E
The total age of all family members = 30 × 14 = 420
 
New baby born and after 4 years the total age of all the members = 420 + 15 × 4
 
= 420 + 60 = 480

Reqd average =  480  = 32 years
15

Hence, option E is correct.
 
2
Mahima bought 20 kg pasta for Rs 30 per kg, m kg pasta for Rs 35 per kg and (m + 4) kg pasta for Rs 25 per kg. She mixed all type of pasta together and the average cost price of 1 kg pasta is Rs 29.6. Find the quantity of pasta that is bought at Rs 25 per kg.
» Explain it
E
According to the question,

20 × 30 + m × 35 + (m + 4) × 25 = 29.6 × (20 + m + m + 4)

600 + 35m + 25m + 100 = 29.6 × (24 + 2m)

700 + 60m = 710.4 + 59.2m

710.4 – 700 = 60m – 59.2m

10.4 = 0.8m

m = 13 

Quantity of pasta that is bought at Rs 25 per kg = 13 + 4 = 17 kg

Hence, option E is correct.
3
The average salary per head of all the workers of an office is Rs 95. The average salary of 15 officer is Rs 525 and the average salary of the rest is Rs 85. Find the total numbers of workers.
» Explain it
B
Let total no. of workers = x
 
Total salary = x × 95       ..... (i)
 
again, as per the question
 
Total salary = 15 × 525 + (x – 15) × 85         ..... (ii)
 
From (i) & (ii)
 
⇒ x × 95 = 15 × 525 + (x – 15) × 85
 
⇒ 95x – 85x = 7875 – 1275
 
⇒ 10x = 6600
 
⇒ x = 660

Hence, option B is correct.
4
The average weight of three students A, B and C is 88.5kgs while the average weight of the other three students, D , F and G is 83.5 kg. What is the average weight of A, B, C, F and J?
» Explain it
D
We have to determine the average weight of
 
A, B, C, F and J.
 
But this can't be determined as we
 
don't know the Score of J.
 
Hence the data is inadequate to solve the given question.

Therefore, option (D) is correct.
 
5
There are 25 students in a class and the average of their ages is 15 years. The average age of the first 12 students is 14 and the average age of the last 12 students is 16. If the age of Amrutha is 5 years more than the age of 13th student, find the age of Amrutha.
» Explain it
C
Total age of 25 students = 15 × 25 = 375

Total age of first 12 students = 12 × 14 = 168

Total age of last 12 students = 12 × 16 = 192

The age of 13th student = 375 – ( 168 + 192)

= 375 – 360 = 15

Amrutha's age = 15 + 5 = 20 years

Hence, option C is correct.


In this Arithmetic Average Quiz 10, you will practice question relation to bank and Insurance like  SBI Clerk Pre, IBPS Clerk Pre, IBPS RRB Pre, Railways, UIIC, LIC, NIACL, NICL, OICL and other competive exams

Here we are going to discuss about Average concept, Tricks and Shortcuts for all bank, SSC, Insurance and Railways Exams.

Average is most important part for all competitive exams, in each exam generally one has asked from Average chapter.

Let discuss about Average with suitable examples

Introduction:

An average or an arithmetic mean of given data is the sum of the given observations divided by number of observations.

Average =  ( Sum of observations ) .
Numbers of observations

For example, if a batsman scores 35, 45 and 37 runs in first, second and third innings respectively, then his Average runs in 3 innings 

 = 35 + 45 + 37  = 39 runs.
3

Therefore, the two mostly used formulas in this chapter are:

Average Total of data
No. of data

                         &

 
Total = Average × No. of data

Properties of Average:


1. Average of a given data is less than the greatest observation and greater than the smallest observation of the given data.
For example, average of 3, 7, 9 and 13

3 + 7 + 9 + 13  =  32  = 8
4 4

Clearly, 8 is less than 13 and greater than 3.

2. If the observations of given data are equal, then the average will also be the same as observations.
For example, average of 6, 6, 6 and 6 will be 6 because

6 + 6 + 6 + 6  =  24  = 6
4 4

3. If 0 (zero) is one of the observation of a given data then that 0 (zero) will also be included while calculation average.
For example, average of 3, 6 and 0 is 3 because

3 + 6 + 0  =  9  = 3
3 3

Remember

• If the value of each item in a group is increased/decreased by the same value x, then the average of the group also increases/decreases by x. For instance, if the income of each person in a group increases by 15, the average income of the group also increases by Rs. 15.
This is valid only when the value of each item increases/decreases by the same amount.

• If the average age of group of people is x years, then their average age after n years will be (x + n) and their average age n years ago would have been (x – n) years.
This is because with each passing year, each person’s age increases by 1 and vice versa.

• If the value of each item in a group is multiplied/divided by the same value x (where x ≠ 0 in the case of division), then the average of the group also gets multiplied/divided by x.

Ex. The average weight of 4 men is increased by 3 kg when one of them who weighs 120 kg is replaced by another man. What is the weight of the new man?

Sol. If the average is increased by 3kg, then the sum of weights increases by 3 × 4 = 12 kg.

And this increase in weight is due to the extra weight included due to the inclusion of new person.

 Weight of new man = 120 + 12 = 132 kg

============================================================

What is Testzone?
Testzone is India's leading Test Series website for all major competitive exams like SBI Clerk Pre 2018, SBI Clerk Mains 2018, SBI PO Pre 2018, SBI PO Mains 2018, IBPS Clerk Pre 2018, IBPS Clerk Mains 2018, IBPS RRB Office Assistant Pre and Mains 2018, IBPS RRB Scale 1 Pre and Mains 2018, RBI Assistant Pre and Mains 2018, IBPS PO Pre 2018, IBPS PO Mains 2018, etc. Currently, Testzone is offering SBI Clerk 2018 Test Series, Syndicate Bank PO 2018 Test Series, Canara Bank PO 2018 Test Series, SSC CHSL 2018 Test Series, SSC CGL Tier 1 2018 Test Series and other upcoming Test Series for an unbelievable price of Rs 99 for a year.

Link to: SBI Clerk Pre 2018 Test Series
Link to: Syndicate Bank PO 2018 Test Series
Link to: Canara Bank PO 2018 Test Series
Link to: SSC CHSL 2018 Test Series
Link to: SSC CGL Tier 2 Test Series