Question

Given the set: {−6,x,7,11,29,−4,−5}, for what x would the mean of the set be -9?

Answer 1

mean = sum of observation / number of observation

$- 9 = \frac{ - 6 + x + 7 + 11 + 29 - 4 - 5}{7} = \\ - 9= \frac{ - 15 + 47 + x}{7} \\ - 9 \times 7 = 32 + x \\ - 63 = 32 + x \\ x = - 63 - 32 \\ x = - 95$

x = -95