Answer:
the answer is your teacher just wanted to draw a triangle and get paid for it.
let's say the original price is "x", so that'd be the 100%.
and we know that is discounted by 30%, 100% - 30% = 70%, we know the discounted price is 206.50, so namely 206.50 is the 70% then.
if 206.50 is 70% of "x", what is "x"?

So the difference between 45 and 10 is..
35 (omygad)
You have to divide 35/5 to get the average drop in the temperature PER HOUR, meaning 7 degrees per hour.
Answer: i'm pretty sure she got 35 the second time. hope this helps