Answer:
Ten hundredths in standard from is 0.1.
Hey there :)
To find the slope with <em>two points</em> we will need to use the equation 

( 3 , -20 ) ( 5 , 8 )
Here is what the equation should look like when replaced with the numbers (<em>it will be a fraction</em>) :

We know that <em>two negatives</em> cancel out and make a positive, so the numerator would actually be 8 + 20.
Solve the fraction and we get 
28 <em>divided</em> by 2 is 14. The slope is 14.
19/15, look at the attachment for work
37.5% of 20 is 7.5 so the answer is 37.5%
Think of it as a problem with only the equations so we know the exact numbers of each ride and each cost now we need to do some division and multiplication
2 games and 4 rides