Question

The mean height of 5 students is 61.8. If one of the students leaves, the mean height becomes 60. What is the height of the absent student?

Answer 1

The total for 5 students is 309 inches.

4 * 60 = 240

309 - 240 = ?

Answer 2

The way to find the mean is by adding up all the different values and then dividing by the total number. If there are five numbers you can set up an algebraic equation like:

x/5 = 61.8

then you can set up a new equation to solve for the height without the absent student:

h/4 = 60

Then you subtract the second value from the first, to get the difference, which is the height of the absent student.

Answer 3

(5*61.8 - 1*x)/4 = 60
309 -x = 240
x = 69