Question 575616
your given average equation is as shown below
{{{(16+18+12+23+x)/5=18}}}
this is interpreted from adding up all the scores dividing by the number of scores to get the average of the scores.
{{{(16+18+12+23+x)/5=18}}} solve for x, add like terms
{{{(69+x)/5=18}}} multiply by 5
{{{69+x=90}}} subtract 69
{{{x=21}}}