Question

The mean of 14 numbers is 49. Removing one of the numbers causes the mean to decrease to 43. What number was removed?

Answer 1

126 was removed.

Explanation:

The total before division took place was

Total = mean * 14

mean = 49

Total = 49 * 14

Total = 685

Now you subtract x from the total

685 - x

And divide by 13 [one number is missing]

(685 - x)/13

and the result = 43

(685 - x ) / 13 = 43 Multiply both sides by 13

685 - x = 43 * 13

685 - x = 559 Subtract 685 from both sides

- x = - 126 Multiply by - 1

x = 126