Question

Find n so that mean of the data set is 140. (120, 145, 130, 80, 95, 100, 340, n)

Answer 1

Answer: n is 110

Explanation:

Formular:

`mean = ( \sum(n_(1), \: n _(2), \: ...n_(n) ) )/(n) \\`

therefore:

`140 = ((120 + 145 + 130 + 80 + 95 + 100 + 340 + n))/(8) \\ \\ (8 * 140) = 1010 + n \\ 1010 + n = 1120 \\ n = 1120 - 1010 \\ n = 110`