Developing an Equation from Average Costs

Tucker Pup$$s Pet Resort offers dog boarding services in Chicago. Assume that in March, when dog$-$days occupancy was at an annual low of $150$ days, the average cost per dog$-$day was $$65.$ In July, when dog$-$days were at a capacity level of $600,$ the average cost per dog$-$day was $$20.$

$($a$)$ Develop an equation for monthly operating costs.

Total cost $=$ $Answer $1$

$9,000$

$+$ $Answer $2$

$5$

$*$ X

$($b$)$ Determine the average boarding cost per dog$-$day at an annual volume of $4,500$ dog$-$days.

$Answer $3$

$7$