It took Elizabeth 10 days to read a 450-page biography. She read about the same number of pages of the book each day. How many pages did Elizabeth read each day?

1 Answer
Dec 31, 2016

The mean count of pages is 45 per day


Using ratio

#("page count")/("day count") -> 450/10#

But we need the page count for 1 day. Consequently we need to change the 10 days to 1 day.

Divide both the top and bottom by 10

#("page count")/("day count") -> 450/10-=(450-:10)/(10-:10) = 45/1#

Note that #-=# means 'equivalent to'