Question

Vani ma'am has three Tatva books, one for chemistry, physics and biology. The chemistry book had 120 pages, the physics book has 10% more pages and the biology book has 10% fewer pages. In a class, she went through 2.5%, 25% and 50% of the pages in the chemistry, physics and biology books respectively, then how many pages in total did she cover in the class?​

Answer 1

Step-by-step explanation:

25% is the right answer I'm really sure

Answer 2

Given - Number of pages in chemistry, physics and biology - 120, 10% more and 10% fewer.

Percentage of pages she covered in chemistry, physics and biology - 2.5%, 25% and 50%.

Find - Total number of pages Vani ma'am cover in class.

Solution - Number of pages in chemistry book : 120

Number of pages in physics book : 120 + 10/100*120 = 120 + 12 = 132.

Number of pages in biology book : 120 - 10/100*120 = 120 - 12 = 108.

Number of pages covered in chemistry book : 120*2.5/100 = 3.

Number of pages covered in physics book : 132*25/100 = 33.

Number of pages covered in biology book : 108*50/100 = 54.

Hence, total number of pages covered in class = 54 + 33 + 3 = 90.