At least one book from the shelf?
Explanation:
There are 5 identical Maths books, 4 identical Reasoning books and 3 identical English books.
For Math books:
Either we can pick no Math book or only 1 book or 2 books or 3 books or 4 books or 5 books i.e., we can pick Math books in (5 + 1) = 6 ways.
Similarly for Reasoning, number of ways of picking books = (4 + 1) = 5 ways, and
For English, number of ways of picking books = (3 + 1) = 4 ways.
∴ Total Number of ways of picking books = (5 + 1)(4 + 1)(3 + 1) = 120 ways.
Out of these 120 ways, there would be 1 possibility when no book is picked.
∴ Total Number of ways of picking at least 1 book = 120 – 1 = 119 ways.
Hence, 119.
» Your doubt will be displayed only after approval.
Help us build a Free and Comprehensive Preparation portal for various competitive exams by providing us your valuable feedback about Apti4All and how it can be improved.