Question

After reading $\frac{7}{9}$ of a book, 40 pages are left. How many pages are there in the book ?

Answer 1

Let number of pages =1

Then no. of pages read = $\frac{7}{9}$

and no. of pages left = $1-\frac{7}{9}=\frac{9-7}{9}=\frac{2}{9}$

If $\frac{2}{9}$ pages are left then total number of pages = 1

and 1 page is left then total number of pages = $1÷\frac{2}{9}=1\times \frac{9}{2}$

and if 40 pages are left then total number of pages = $\frac{9}{2}\times 40=\frac{360}{2}=180Ans.$