Question

Mr and Mrs Waugh want to use a caterer for a birthday party for their twin sons. The manager says the cost for a family of four would be $160. However, the sons want to invite 8 friends, making 12 people in total. The cost for this would be $360. If the total cost in each case is made up of the same cost per person and the same fixed cost, find the cost per person and the fixed cost.

Answer 1

$60 fixed price $25 per person

Explanation:

x=price per person

c= fixed cost

4x+c =160

12x+c=360

I will multiply the first by -1:

-4x -c=-160

12x+c=360

ADD BOTH:

8x = 200

x=25 ($25 per person)

25*4=100

160-100 = 60 (fixed cost =60)

25*12=300

300 + 60(fixed cost) = 360