Question

A taxi charges a flat rate of $3.00, plus an additional $0.50 per mile. Carl will only take the taxi home if the cost is under $10, otherwise he will take a bus. Carl is 15 miles from home. Explain how to write and solve an inequality to determine if Carl will take the taxi or a bus.

Answer 1

Let x be the number of miles. The taxi cost is 3 + 0.50x. Carl will take the taxi only if this cost is under $10, so

3 + 0.50x < 10.

Solve: 0.50x < 7, so x < 14.

Carl is 15 miles from home, and 15 is not less than 14, so he will not take the taxi. (Check: cost = 3 + 0.50·15 = $10.50 > $10.) Therefore he will take the bus.