Problema Solution

A class wants to go on a trip. Each bus holds 40 students and 3 teachers and cost $1200 to rent. Each van holds 3 students and 1 teacher and cost $100 to rent. The school has at least 400 students wanting to go but at most 36 teachers. What is the minimum transportation cost?

Answer provided by our tutors

if only buses were used:

400 / 40 = 10 buses

10*1200 = $12,000

10*3 = 30 teachers


if only vans were used:

400/3 = 133 vans

133*100 = $13,300

133*1 = 133 teachers


clearly, we want to maximize the number of buses but it's cheaper to add one van rather than one bus


use 10 buses and get an extra van if more than 30 teachers decide to go


$12,000 + $100 = $12,100 as a minimum cost if all 36 teachers attend