Problem Solving: Working Backwards

Question

On the first day of vacation, you read one-quarter of a novel. On the second day, you read half of the remaining pages. On the third day, you read the last 135 pages of the novel. 

 

How many pages does the novel have?

 

How many pages did you read by the end of the second day? 

Answer 1

"On the third day, you read the last 135 pages of the novel. "

 

"On the second day, you read half of the remaining pages."   So, you read 135 pages, which was half of the 270 remaining pages.

 

"On the first day of vacation, you read one-quarter of a novel."  There was 3/4ths (that is, 270 pages) remaining.

 

The novel has 360 pages.

     90 read on first day.

    135 read on second day.

    135 read on third day.

  ---------------------------

    360 pages total

 

By the end of the second day,  you have read 225 pages.