A cricketer has an average of 88 runs over 10 innings. If he scores 219 runs in the 11th inning, by how many runs (rounded off to the nearest whole number) does his average score increase?

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).