Question

A toll bridge charges $1.00 for passenger cars and $2.25 for other vehicles. suppose that during daytime hours, 70% of all vehicles are passenger cars. if 20 vehicles cross the bridge during a particular daytime period, what is the resulting expected toll revenue? [hint: let x = the number of passenger cars; then the toll revenue h(x) is a linear function of x.]

Answer 1

We're not quite sure what the point of the hint is, since we're interested in total revenue, not just that from passenger cars.

For 20 vehicles, we expect to see 0.70×20 = 14 passenger cars and 6 other vehicles. Then the revenue will be
14×$1.00 + 6×$2.25 = $14.00 + 13.50 = $27.50