If the mean of 4 observations is 20, when a constant 'C’ is added to each obse

Question

If the mean of 4 observations is 20, when a constant 'C’ is added to each observation, the mean becomes 22. The value of C is :

Options:

A . –2

B . 2

C . 6

D . 4

Answer: Option B
Answer: (b)4C = 22 × 4 – 20 × 4 = 88 – 80 = 8 ⇒ C = $8/4$ = 2

Was this answer helpful ?

Next Question

More Questions on This Topic :

Question 1. The average of five numbers is 27. If one number is excluded, the average becomes 25. The excluded number is :....

Question 2. The average of five numbers is 7. If three new numbers would be added, then the new average comes out to be 8.5. What is....8.5. What is the average of those three new numbers?

Question 3. The average of 50 numbers is 38. If two numbers namely 45 and 55 are discarded, the average of the remaining numbers is ....are discarded, the average of the remaining numbers is :

Question 4. There were 35 students in a hostel. If the number of students is increased by 7 the expenditure on food increases by Rs.....What was the initial expenditure on food per day ?

Question 5. The average of 6 observations is 45.5. If one new observation is added to the previous observations, then the new averag....then the new average becomes 47. The new observation is

Question 6. The average monthly salary of 19 members of a group is Rs. 16000. If one more member whose monthly salary is Rs. 20000 j....the group, then the average salary of the group is

Question 7. The average monthly expenditure of a family for the first four months is Rs.2570, for the next three months Rs.2490 and ....average monthly income of the family during the year is

Question 8. Average income of ‘A’ and ‘B’ is Rs.200 and average income of ‘C’ and ‘D’ is Rs.250. The average income ....The average income of A, B, C and D is

Question 9. A man spends Rs.1800 monthly on an average for the first four months and Rs.2000 monthly for the next eight months and s....and saves Rs.5600 a year. His average monthly income is

Question 10. The average expenditure of a man for the first five months is Rs.1200 and for the next seven months is Rs.1300. If he sa....Rs.2900 in that year, his monthly average income is :

Chapter 1 - GLOBAL STEEL SCENARIO & INDIAN STEEL INDUSTRY Part 1 : (13-04-2024) INDUSTRY AND COMPANY AWARENESS (ICA)

Direction Sense Test Part 1 Reasoning (Hindi)

Chapter 1 - RMHP / OHP / OB & BP Part 1 : (14-02-2024) GPOE

Cube & Cuboid Part 1 Reasoning (Hindi)

Data Interpretation (DI) Basic Concept Reasoning (Hindi)

Counting Figures Part 1 Counting Of Straight Lines Reasoning (Hindi)

Sail E0 free webinar Webinars

Real Numbers Part 7 Class 10 Maths

Real Numbers Part 1 Class 10 Maths

Polynomials Part 1 Class 10 Maths

DSP Combined 1 Free Revision Test SAIL JO E-0

GPOE / GPA Combined 1 Free Revision Test SAIL JO E-0

BSP Plant Specific Review Test SAIL JO E-0

BSL Combined 1 Free Revision Test SAIL JO E-0

GFM Combined 1 Free Revision Test SAIL JO E-0