If we let 
be the number of pages read in 1 hour, then in 7 hours Doug reads 
pages. We know that this number of pages is 231, so we have
The result can be shown in both exact and decimal forms.
Exact Form:
2
3
Decimal Form:
0.
¯
6
Answer:
8. 5/6
9. 6.25, 6 and 1/4
10. 14.4
Step-by-step explanation:
Sorry that this is a little late. All of these problems end up with the same process to get to the answer. Since you want to find the rate, you would want to divide the amount of time taken by itself to find the unit rate. So basically, 8. would be 20 cm in 24 hours. You would divide both by 24 and you get 20/24 cm in 1 hour. and then you simplify the fraction and boom, there's your answer.
