Final answer:
The rate of change of profit between 210 and 310 units is $5.50 per unit. The equation for the profit function is P(x) = $5.50x - $665. Using this function, the predicted profit for 350 units sold is $1260.
Step-by-step explanation:
To find the rate of change of profit, we can use the profit values at 210 units and 310 units and apply the formula for the slope of a line since the profit function is linear. The formula is (change in profit)/(change in units sold) = (profit2 - profit1)/(units2 - units1).
a) Using the given values, the rate of change is ($1040 - $490)/(310 - 210) = $550/100 = $5.50 per unit.
b) The profit function can be represented in the form of P(x) = mx + b, where m is the rate of change we just calculated and b is the y-intercept. To find b, we can use one of the given points, for example, (210, $490), and solve: $490 = $5.50(210) + b. This gives us b = $490 - $1155 = -$665.
So, the profit function equation is P(x) = $5.50x - $665.
c) To predict the profit from the sale of 350 units, we substitute x with 350 into the profit function: P(350) = $5.50(350) - $665 = $1925 - $665 = $1260.
Therefore, the predicted profit from the sale of 350 units is $1260.