Question

question number Vi)please show the steps

Answer 1

c)8 is the answer for your question

Answer 2

sum of n natural numbers (s)
$s = \frac{n(n + 1)}{2}$
mean
$\bar{x} = \frac{n + 1}{2}$
now
$\frac{n + 1}{2} = \frac{n + 8}{4} \\ 2n + 2 = n + 8 \\ n = 6$
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