Question

Item 10 A restaurant earns $1240 on Friday and $921 on Saturday. Write and solve an equation to find the amount xx (in dollars) the restaurant needs to earn on Sunday to average $1000 per day over the three-day period. Write your equation so that the units on each side of the equation are dollars per day.

Answer 1

Let the restaurant need to earn x dollars on Sunday, to average 1000$/day .

The average earning over the 3 days is
`(1240+921+x)/(3)= (2161+x)/(3)` dollars.

we equalize this expression to $1000:


`(2161+x)/(3) =1000\\\\ 2161+x=3000\\\\x=3000-2161\\\\x=839` dollars


Thus the equation is :
`(1240+921+x)/(3)(\$/day)=1000(\$/day)`