Average- Aptitude Questions and Answers

View in English View in Hindi

What is the range of the data given below- 20, 35, 70, 65, 45, 95, 15, 80

A)
15

B)
80

C)
45

D)
95


Correct Answer :

80


Explanation :

Ordering the data from least to greatest, we get:
15, 20, 35, 45, 65, 70, 80, 95

highest - lowest = 95 - 15 = 80
The range is 80

What is the Arithmetic Mean of first 100 natural numbers?

A)
50

B)
50.5

C)
51

D)
55


Correct Answer :

50.5


Explanation :

Mean=(Total Sum of all the Values)/(No of Values)

The Sum of first ’n' natural numbers is given by,Sum=n*(n+1)/2
then, Mean=[n*(n+1)/2] / n
=n*(n+1) / 2*n

So,the mean of first 100 natural numbers, Mean=100*101 / 2*100
=101/2
=50.5

Find the mean, median, mode, and range for the following list of values ?
13, 18, 13, 14, 13, 16, 14, 21, 13

A)
15, 14, 13 and 8

B)
15, 14, 14 and 13

C)
13, 13, 13 and 13

D)
15, 14, 13 and 15


Correct Answer :

15, 14, 13 and 8


Explanation :

Mean :To find the mean, add all the numbers together then divide by the number of numbers.
Mean = (13 + 18 + 13 + 14 + 13 + 16 + 14 + 21 + 13) / 9 = 15

Median:To find the median, order the numbers and see which one is in the middle of the list.
Reordered = 13, 13, 13, 13, 14, 14, 16, 18, 21 - the middle term is 14 ie Median=14

Mode:To find the mode, order the numbers lowest to highest and see which number appears the most often.
13 is the number which appears the most often

Range:To find the range, subtract the lowest number from the biggest number.
Reordered = 13, 13, 13, 13, 14, 14, 16, 18, 21
Range = ( 21- 13 ) = 8

The average of the first 10 prime numbers?

A)
10.1

B)
10

C)
12.9

D)
13


Correct Answer :

12.9


Explanation :

First 10 prime numbers are 2,3,5,7,11,13,17,19,23,29

Average =(2+3+5+7+11+13+17+19+23+29)/10
=129/10
=12.9

Two years ago, the average age of a family of 8 members was 18 years. The average age of the family after the birth of a child is the same today. How old is the child?

A)
2 years

B)
1*(1/2) years

C)
1 year

D)
2*(1/2) years


Correct Answer :

2 years


Explanation :

As given, after birth of child average age is same ie 18 years, hence age of child is 2 years

Or

2 years back total age of 8 members = 18 * 8 = 144 years
Total present age of 8 members = 144 + 2*8 = 160 years
Now, a child born, average age reamin same, that is Average age of 9 people = 18
Toatl age of 9 people = 18 * 9 = 162 years.
Age of child = 162 - 160 = 2 years

The average of 9 full numbers is 11 but after calculation, it was seen that while computing by the mistake the 23 was written to 32. What will be the new average after making appropriate amendment?

A)
10

B)
9

C)
10.1

D)
9.5


Correct Answer :

10


Explanation :

The average of 9 numbers = 11
Therefore, the total is = 9*11 =99
But by mistake the 23 was written 32
So, new avarage =(99+23-32)/9
=90/9
=10

The average of first three numbers out of four numbers are 18 and the average of the last three numbers is 16. If the last number is 19, then the first number is?

A)
19

B)
18

C)
20

D)
25


Correct Answer :

25


Explanation :

Let the numbers are A, B ,C and D, then as given
A+B+C=18*3=54
B+C+D=16*3=48
After resolving the above equations -
A-D=6
the last number is 19 ie D=19
So, A=6+19 =25

The average of seven consecutive numbers is 20, then the largest number in those numbers is?

A)
24

B)
23

C)
22

D)
20


Correct Answer :

23


Explanation :

Let the numbers are X to ..(X+6).
As given,
X+(X+1)+(X+2)+(X+3)+(X+4)+(X+5)+(X+6)=20*7
7*X+21=140
7*X=119
X=17
Hence, the largest number is=(X+6) =17+6 =23

A man bought 13 items worth Rs 70, 15 items worth Rs 60 and 12 items worth 65 rupees. Average value per item is?

A)
60.25

B)
64.75

C)
65.75

D)
63.25


Correct Answer :

64.75


Explanation :

Average value=(13*70)+(15*60)+(12*65) / (13+15+12)
=2590/40
=64.75

If the average of 20-digit X1, X2, ... X20 is Y, then what is the average of X1-101, X2-101, X3-101 ..... X20-101?

A)
Y-20

B)
Y-101

C)
20Y

D)
101Y


Correct Answer :

Y-101


Explanation :

Average = (X1+ X2+X3 +... +X20)/20 - (101*20)/20
=Y-101

The average of 27 numbers is 60. If instead of 28 one number has changed to 82, what will be the average?

A)
56

B)
58

C)
62

D)
64


Correct Answer :

62


Explanation :

New average = (27*60)- 28 + 82 / 27
=1620-28+82 / 27
=1674/27
=62

A factory buys 8 machines.3 Machine A, 2 Machine B and rest Machine C. Prices of the machines are 100000, 80000 and 45000 respectively.Calculate the average cost of these machines?

A)

74375


B)

75000


C)

75625


D)

72875



Correct Answer :

74375


Explanation :

Average cost of all the machines =(3*100000 + 2*80000 + 3*45000) / 8
= 595000/8
= 74375

The mean of 5 numbers is 15. If one more number is included, the mean of the 6 numbers becomes 17. What is the included number?

A)
24

B)
25

C)
26

D)
27


Correct Answer :

27


Explanation :

Sum of these 5 numbers = Mean*Total Number = 15*5 = 75
Let the number included is x.
As given
75+x / 6 = 17
75+x = 17*6
x = 102-75
x = 27

The mean marks obtained by 300 students in a subject are 60. The mean of top 100 students was found to be 80 and the mean of last 100 students was found to be 50. The mean marks of the remaining 100 students are?

A)
70

B)
65

C)
60

D)
50


Correct Answer :

50


Explanation :

Total marks of remaining(middle 100) students = 300*60 - 100*80 - 100*50
= 18000 - 8000 - 5000
= 18000 - 13000 = 5000

Hence, Mean marks of remaining 100 students = 5000/100 = 50

In an asymmetrical distribution, of the mean and median of the distribution are 270 and 220 respectively, then the mode of the data is?

A)
120

B)
220

C)
380

D)
370


Correct Answer :

120


Explanation :

Mode = 3 Median - 2 Mean
= 3*220 - 2*270
= 660 - 540
= 120

Let a, b, c, d, e, f, g be consecutive even numbers and j, k, l, m, n be consecutive odd numbers. What is the average of all the numbers?

A)
3(a + n) /2

B)
(5l + 7d )/4

C)
(a + b + m + n)/4

D)
(7d + 5l) /12


Correct Answer :

(7d + 5l) /12


Explanation :

Let a = x (even)
b = x + 2, c = x + 4, d = x + 6
e = x + 8, f = x + 10, g = x + 12
a + b + c + d + e + f + g = 7x + 42
= 7(x + 6) = 7d
And j = y (odd), k = y + 2,
l = y + 4, m = y + 6, n = y + 8
j + k + l + m+ n = 5y + 20
= 5( y + 4) = 5l

Average of all the numbers = (7d + 5l) /12

Latest Updates

Apache Tomcat

What is the difference between Apache Tomcat server and Apache web server?

MS-DOS

What is the full form of DOS?

Explain the use of help DOS Command?

How we can create a directory in DOS?

Analogy

Riddle:Solve

Limp:Walk

Molecule:Atoms

Misfortune:Catastrophe

Pipes and Cistern

A tank can be filled by one tap in 10 minutes and by another in 30 minutes. Both the taps are kept open for 5 minutes and then the first one is shut off. In how many minutes more is the tank completely filled?

Simplification

Assume that a sum of money is divided equally among n girls. Each girl will receive $60. If another girl is added to the group and the sum is divided equally among all the girls, each child girl gets a $50 share. What is the sum of money?

Problems on Trains

A 300 meter long metro train crosses a platform in a metro station in 39 seconds while it crosses a lamp post in 18 seconds. What is the length of the platform?

Problems on Ages

In a group of 7 people, the average age is found to be 17 years. Two more people joined with an average age 19 years. One person left the group whose age was 25 years. What is the new average age of the group?

Profit and Loss

Irvin sold a book at a profit of 12%. If Irvin had sold it for Rs 18 more, then 18% would have been gained. Find the cost price?

Chemistry

Non stick cooking utensils are coated with?

The group of metals Co, Ni, Fe may best called as?

General Knowledge of India

'Kanchipuram' is in which of the following states?

General Knowledge of World

In which year was Pulitzer Prize established?

Indian History

The roads of cities in the Indus Valley Civilization generally divided the city into?

Latest Job Notifications

Jobs in West Bengal

इंडियन पोस्ट सर्विस Indian Post Service - 2357 पद - 19/08/2021 अंतिम तिथि - पश्चिम बंगाल पोस्टल सर्कल

Banking Jobs

भारतीय स्टेट बैंक State Bank of India(SBI) - 6100 पद - 26/07/2021 अंतिम तिथि - CRPD/APPR/2021-22/10

SSC Recruitment

कर्मचारी चयन आयोग Staff Selection Commission(SSC) - 25271 पद - 31/08/2021 अंतिम तिथि

Jobs in Madhya Pradesh

राष्ट्रीय स्वास्थ्य मिशन मध्य प्रदेश National Health Mission MP(NRHM) - 5215 पद - 22/06/2021 अंतिम तिथि

Jobs in Punjab

पंजाब स्टेट पावर कॉर्पोरेशन लिमिटेड Punjab State Power Corporation Limited (PSPCL) - 2632 पद - 20/06/2021 अंतिम तिथि

Jobs in Chhattisgarh

स्वास्थ्य सेवा निदेशालय, छत्तीसगढ़ Department of Health & Family Welfare, Chhattisgarh - 267 पद - 26/06/2021 अंतिम तिथि

Government Jobs

दिल्ली सबऑर्डिनेट सर्विस सिलेक्शन बोर्ड Delhi Subordinate Services Selection Board(DSSSB) - 5807 पद - 03/07/2021 अंतिम तिथि

Jobs in Madhya Pradesh

राष्ट्रीय स्वास्थ्य मिशन मध्य प्रदेश National Health Mission MP(NRHM) - 2850 पद - 31/05/2021 अंतिम तिथि

Government Jobs

इंडियन पोस्ट सर्विस Indian Post Service - 4368 पद - 29/05/2021 अंतिम तिथि

दिल्ली सबऑर्डिनेट सर्विस सिलेक्शन बोर्ड Delhi Subordinate Services Selection Board(DSSSB) - 7236 पद - 24/06/2021 अंतिम तिथि