Question

The five marathon runners weigh an average weight of 92 pounds, Nicole weighs 89 pounds, Jon weighs 95 pounds, Jenny and Kim weigh 90 pounds each, How much does Jordin weigh?

Answer 1

Jordin weighs 96 pounds

Explanation:

The Mean Value of a Data Set

The mean or average of a data set is found by adding all numbers and then dividing by the number of values in the set. Written as a formula:

`\displaystyle \bar x=(\sum x_i)/(n)`

Where xi is the value of each data and n is the total number of values.

We are given the average weight of n=5 marathon runners:

`\bar x=92`

Multiplying the formula by n and expanding the sum:

`n\bar x=\sum x_i=x_1+x_2+x_3+x_4+x_5`

We are given the weighs of four of the runners:

`5*92=89+95+90+90+x_5`

`460=364+x_5`

Solving for x5:

`x_5 = 460-364=96`

Jordin weighs 96 pounds