Mathematics textbook for Class VI has 320 pages. The chapter ‘symmetry’ runs from page 261 to page 272. The ratio of the number of pages of this chapter to the total number of pages of the book is
11 : 320
3 : 40
3 : 80
272 : 320
What is asked?
We need the ratio of the pages in the chapter “Symmetry” to the total pages of the book.
Find how many pages are in the chapter.
The chapter starts at page 261 and ends at page 272. This is inclusive, so we count both 261 and 272.
First find the difference:
(272 - 261 = 11)
Now include both ends by adding 1:
(11 + 1 = 12)
So, pages in the chapter = 12
Write the ratio (chapter pages : total pages).
(12 : 320)
Simplify the ratio.
Both numbers are divisible by 4.
Divide each by 4:
( dfrac{12}{4} = 3 )
( dfrac{320}{4} = 80 )
Simplified ratio = (3 : 80)
Match with the options.
The correct option is 3 : 80, which is Option C.