25.5k views
3 votes
Your friend has $90 when he goes to the fair. He spends $5 to enter the fair and $15 on food. Rides at the fair cost $1.50 per ride. Which function can be used to determine how much money he has left over after x rides?

2 Answers

3 votes
Easy, if he has $90 in ALL

and he spends $5 and $15

$20 in total

take, 90-20=70

So now he only has $70 left.

If each ride costs $1.50, then he's losing money.

So, y=-1.50x+70

So around the 47th ride he will have no more money.
User Chriga
by
6.9k points
4 votes

Answer:


f(x)=70-1.5x or
f(x)=-1.5x+70

Explanation:

Money taken to the fair = $90

Money spent to enter the fair = $5

Money spent on food =$15

Total he spent now is given by :
5+15=20 dollars

Let the number of rides be = x

And he spends $1.50 on each ride, so total money spent on rides =
1.50x

Total money including rides can be shown as:


20+1.50x

Now money left after this will be
90-(20+1.50x)

=
70-1.50x

Let f(x) denotes the function used to determine the money left after rides,


f(x)=70-1.5x or
f(x)=-1.5x+70

User Bruno Shine
by
7.8k points