तीन संख्याओं का औसत 20 है। यदि दो संख्याएँ 12 और 28 हैं, तो तीसरी संख्या है:

The average of 100 numbers is 40. If one of the numbers, 30, is replaced by 70 while keeping the other numbers same, what is the new average?

The arithmetic mean of 22.5, 56, 42.5, 2x + 1, x - 2, 3x, and 36 is 30. Find the value of x (where x > 0).

The average age of a team of 13 players is 30 years. If the age of the coach is included, the average age increases by 1.8 years. What is the age of the coach?

The average of 17 consecutive even numbers is A. If the next 19 even numbers are also included, what will be the average of all 36 numbers?

The arithmetic mean of 22.5, 56, 42.5, 2x + 1, x - 2, 3x, and 36 is 30. Find the value of x (where x > 0).

The average of 31 results is 65. If the average of the first 16 results is 61 and the average of the last 16 results is 69, then what is the value of the 16th result?

Find the average of the squares of the first 8 natural numbers.

At a health club, 60% of the members are women and 40% of the members are men. If the average age of the men is 21 years and the average age of the women is 59 years, what is the average age (in years) of all the members?