how many pages will be in a book

Question

if the first 8 chapters of a book are 13 pages long, how many pages long will the book be if there are 45 chatpers

Answer 1

Hi Allison,

This question is a bit ambiguous. Are the first 8 chapters 13 pages long in total or 13 pages each? If it's 13 pages total, this is a cross-multiplication proportion problem:

13/8= x/45

x=total pages in book

Do the cross-multiplication:

(13*45)=8x

585=8x

x=73.125

Now, if you meant 13 pages each, and we can assume that remains constant throughout the book:

First of all, we need the total length of the first 8 chapters, so this is:

13*8= 104 pages

Now, the book is 45 chapters long, so we subtract:

45-8= 37

to find out how many chapters we still must account for. Now, assuming number of pages per chapter remains constant:

37*8 = 296 pages

That's the page count for the rest of the book, but the question asked for the whole book, so we add:

296 + 104 = 400 pages

I hope this helps.