Answer:
fixed amount is 150
the rate is 6
The formula to calculate the total cost of the caterer is
total cost = 150 × 6 + number of students
Step-by-step explanation:
1. 1050= 150×r+f
2. 750= 100×r+f
• On number 2 you substract on both sides f so you get 750-f=100×r with this you divide on both sides 100 and you get 7,50 -f÷100=r
• Now you can put r into term of number 1 and you get 1050=150x(7,50-f÷100)+f
• If you calculate this to just get a f on one side you get f=150 so this the fixed amount
• Put f in r=7,50-f÷100 so u get r=7,50-150÷100 or r=6 this the rate
• So the formula to calculate the total cost for the caterer is
total cost=150 + 6 × number of students
