The track at Bronwyn’s school is ¼ mile around. If she can do 3 laps in 4 ½ minutes, how fast is she running in miles per hour?

You start by figuring out how fast a lap is so you do
4.5 (4 1/2 miles)/3
=1.5 minutes

Which means it takes her 1.5 minutes to do 1/4 mile so you times that by four to get how long it takes her to run a mile
4x1.5
=6

This means it takes her 6 minutes to run a mile
To get this into miles per hour you divide 60 (because there’s 60 minutes in an hour) by 6 (her mile time)
60/6
=10

Therefore she is running 10 miles per hour

The discount is 8.70 . you dont tell us the percent of tax added so there is no way to find out, unless i'm not seeing anything. without tax its 37.70