Question

14,31 एवं एक अनय सखया का औसत 30 है| तीसरी सख्या कया है|

Answer 1

Hope I will help you

Answer 2

Let,
third no. = x
$\frac{14 + 31 + x}{3} = 30$
$45 + x = 30 \times 3$
45+x=90
x=90-45
x=45 Ans.

Hey mates,I hope it will help you.