Quote:
A taxi service charges a base fare of $5, and a rate of $M per mile for the first 10 miles. Thereafter the rate is $0.5M per mile. There is also a charge of $3 per suitcase. Students traveling from and to the local college get a twenty percent discount on the mileage rates. A is a teacher traveling a distance of 8 miles with one suitcase. B is a student traveling 30 miles with two suitcases from the college to the station.
Select the expression for the difference between the amounts paid by A and B in dollars, and for the amount paid by A in dollars.
Base fare =5, price till 10 miles-10M and price for x after 10 miles is x*M/2
Amount paid by A = Base fare + one suitcase carriage charge + mileage charge for 8 miles
= 5+3+8M=8+8M
Amount paid by B = Base fare + two suitcase carriage charge + 80% of mileage charge for 30 miles
= 5+2*3+0.8(10M+0.5M*20)=11+0.8*20M=11+16M
Difference = 11+16M -(8+8M) = 3+8M