Question

THE AVERAGE OF A LIST OF 10 NUMBERS OS 0.IF 72 AND -12 ARE ADDED TO THE LIST,THE NEW AVERAGE WILL BE WHAT?

Answer 1

It is given that the average of 10 numbers is 0.

$\Rightarrow$$\frac{\mathrm{sum}\mathrm{of}\mathrm{ten}terms}{10}=0$$\Rightarrow sumoftenterms=0*10=0$
According to the question if 72 and (-12) are added to the list then the new average will be

$\frac{sumof10terms+72+(-12)}{12}$
$=\frac{0+72-12}{12}$
$=\frac{60}{12}$
$=5$