2/3 hour . 1 hour = 60 minutes.
2/3 hour = (2/3) * 60
= 40 minutes.
20 pages took (2/3) hour = 40 minutes.
20 pages took her 40 minutes to read.
1 page = 40/20 = 2 minutes.
1 page took her 2 minutes to read.
Step-by-step explanation:

Costs would be nine dollars for the lemons and four dollars for the sugar ($-13.00). You end up losing only fifty cents throughout, so you would have had to sell (.5×25=12.50) 25 cups to pay for all but fifty cents.
Answer is 25 cups