Question

The average of 4 numbers is 10 if 3 numbers are 9 , 11 and 13
What
fourth number​

Answer 1

Answer:

eska solution upper paper me hai

Answer 2

Answer:

$let \: the \: no \: be \: x \: \\ so \: \frac{9 + 11 + 13 + x}{4} = 10 \\ = \frac{33 + x}{4} = 10 \\ = 33 + x = 10 \times 4 \\ = 33 + x = 40 \\ = x = 40 - 33 \\ x = 7$

The answer is 7