Question 358379
Hello, 
Let x be the fifth text score so we can form and equation as:
 (73+79+77+81+x)/5=80
Multiply both sides by 5 toget:
(73+79+77+81+x)=400
Combine like terms:
310+x=400
Subtract 310:
x=90
So a score of 90 is needed. 
Got it?
RJ
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