plz help i need to rase my grade
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The average of anything is calculated by adding up all the terms in the data set and dividing by the amount of terms in the data set.
In this problem,
The average = $1000
the amount of terms = 3
x = the amount earned Sunday
($1073 + $1108 + x) / 3 = $1000
First, multiply both sides by 3
$1073 + $1108 + x = $3000
Add together like terms
$2181 + x = $3000
Subtract $2181 from both sides.
x = $819
The restaurant needs to earn $819 on Sunday to have an average of $1000