## Average

**1.The average weight of a class of 50 students is 48.6 kg. If the average weight of the 20 boys is 54 kg, then find the average weight (in kg) of the girls in the class ( SSC CGL March 2018 )**

- 48
**45**- 146
- 59

**2.Out of three given numbers, the first number is twice the second and thrice the third. If the average of these three numbers is 154, then what is the difference between the first and the third numbers? [Bank Clerks 2011 ]**

- 45
- 59
**168**- 186

**3. Find the average of all the odd numbers and average of all the even numbers from 1 to 55**

**28 and 28**- 23 and 23
- 45 and 55
- 15 and 23

**4. Find the average of all prime numbers between 60 and 90. SSC CHSL 2012 **

- 72
**74.71**- 74
- 73.6

**5. If the average of the ages of Rina and Mousumi is 15, average of the ages of Mousumi and Ritam is 12 and the average of the ages of Rina and Ritam is 13, then the age of Mohan, is**

- 15
**14**- 18
- 20

**6. A cricketer has a certain average of 10 innings. In the 11****th**** inning, he scored 108 runs, thereby increasing his average by 6 runs. What is his new average? UPSC CDS 2016**

- 45
**48**- 51
- 59

**7. Find the average of the following set of scores 253, 124, 255, 534, 836, 375, 101, 443,760 [IBPS Clerk 2011]**

- 508
- 490
**409**- 621

**8.The average speed of an auto is three-fourth the average speed of a train. The train covers 240 km in 12 h. How much distance will the auto cover in 7 h? [IBPS Clerk 2011] **

- 115
- 218
**105**- 361

**9. Ramesh rows in still water with a speed of 4.5 km/h to go to a certain place and come back. Find his average speed for the whole journey, if the river is flowing with a speed of 1.5 km/h. ( SSB Head Constable 2018 )**

**4 km/h**- 7 km/h
- 18 km/h
- 24 km/h

**10. A person covers 40% of his journey at 12 km/h and remaining at 8 km/h. What is his average speed for a complete journey correct to one decimal place in km/h ( DSSSB TGT , SSC CGL ) ?**

- 8
**9.2**- 12
- 11

**11.The average of the ages of Rohan , Riya and Ashok is 43 and the average of the ages of Rohan , Ashok and Rohit is 49. If Rohit is 54 years old, what is Riya ’s age?**

- 30 Years
- 45 Years
- 59 Years
**36 Years**

**12. The mean of 5 observations is 60, the mean of 10 observations is 30 and the mean of 15 observations is 20. The mean of all the 30 observations is-**

- 20
- 58
**30**- 84

**13 . ****The average of 4 numbers is 60 and the 1****st ****number is ****1/3**** of the sum of the remaining three numbers. What is the first number ? ( ****SSC GD 2021 )**

- 47
- 57
**60**- 78

14. **If the average of 5 consecutive odd integers in increasing order is 11 , then the average of the last 3 of them is:**

**13**- 81
- 58
- 59

15. **The average of six numbers is 3.95. The average of two of them is 3.4, while the average of the other two is 3.85. What is the average of the remaining two numbers? (****HSSC , SSC )**

- 3.1
**4.6**- 5.4
- 8.36

**16.****The average salary of all the workers in a factory is Rs. 15,000. The average salary of 12 technicians is Rs. 18,000 and the average salary of the rest is Rs. 12,000 Then, what is the total number of workers in the factory?(IPSC, IBPS , TPC , SSC )**

- 25
**24**- 26
- 27

**17.****There are total 600 students in a school. Average age of boys is 12 years and of girls is 11 years while average age of all students is 11 yrs. And 9 months. Find the number of girls in the school. (SSC, APPSC)**

- 124
**150**- 140
- 193

**18.The average of two numbers is 6.5 and square root of their product is 6. What are the numbers?**

- 1 and 9
- 16 and 25
- 7 and 10
**9 and 4**

**19.A batsman in his 12****th**** inning makes a score of 63 runs and there by increase his average score by 2. What is his average after the 12****th**** innings? ( SSC GD,SSC MTS )**

- 14
- 45
- 60
**41**

**20.The average of 8 consecutive even numbers written in ascending order is 17. What is the average of the last three numbers, 36 and 53? ( SSC CGL , CHSL )**

- 25
- 27
**31**- 39