Question

the temperature for the first 4 days in january was -2 degrees

the mean temperature for the first 5 days in january was 0 degrees

what was temperature on the 5th day ?
URGENT

Answer 1

let's assume the temperature on 5th day be x

We know that :

$\boxed{mean = \frac{sum \: \: of \: all \: \: observations}{number \: \: of \: \: observations} }$

So,

$\hookrightarrow \: 0 = \dfrac{ - 2 + ( - 2) + ( - 2) + ( - 2) + x}{5}$

$\hookrightarrow \: 0 \times 5= - 2 - 2 - 2 - 2 + x$

$\hookrightarrow \: 0 = - 8 + x$

$\hookrightarrow \: x = 8$

Therefore, temperature on the fifth day was x = 8