Answer:
1) Equation's:
2) Number of guest and the charge:
- Cost is same for both at 50 meals. The cost is $1250.
Part 1
Turn sentences into equation's (Let 'y' be total cost and x per meal) :
(i) charges $500 and $15 per meal
(ii) charges $350 and $18 per meal
Part 2
y = y
500 + 15x = 350 + 18x
18x - 15x = 500 - 350
3x = 150
x = 150/3
x = 50
Charge at guest's 50 meal:
y = 500 + 15(50)
y = $1250
Point : (50, 1250)