A local fair charges a $15 entry fee and $1.75 per ride. Dustin has $35 to spend. What is the maximum number of rides Dustin can go on?

Question

(1 mark for two correct 'let' statements, 1 mark for creating correct equation, 1 mark for substituting spending amount in for correct variable and isolating for unknown variable, 1 mark for correct 'therefore' statement with units)

Answer 1

Let x = the number of rides

Let y = the total cost

The total cost is a linear equation:

y = 1.75x + 15

Substituting for y = 35

35 = 1.75x +15

Solving for x

1.75x = 35-15 = 20

x = 20/1.75 = 11.42.8

Therefore the maximum number of rides Dustin can go on is 11, with 42 cent left over.