Question

4. If the mean of the following is 15,find the value of 'a'?
4,5, a, 6, 7 and 9
​

Answer 1

Step-by-step explanation:

$\frac{4 + 5 + a + 6 + 7 + 9}{6} = 15$

$31 + a = 30$

$a = 1$