Question 302992
The mean of five numbers is 6.
 If one of the five numbers is removed, the mean becomes 7.
 What is the value of the number that was removed?
:
Let x = value of the 1st 4 numbers
Let y = value of the number to be removed
:
{{{(x + y)/5}}} = 6
x + y = 5(6)
x + y = 30
then "one of the five numbers is removed, the mean becomes 7.
{{{x/4}}} = 7
x = 4(7)
x = 28
:
Substitute 28 for x in the equation: x + y = 30
28 + y = 30
y = 20 - 28
y = 2, is the value of the number removed