Question

There are five physics and ten maths books, then in how many ways one can select-

• A. $(5+10)$
• B. $5(5\times 10)$
• C. $(5\times 10)$
• D. $5\left(5+10\right)$

Answer 1

Answer: (A), (C)

$(5\times 10)$

When we have to select both, a physics book and a maths book, then total no. of ways it can be selected would follow multiplication rule and hence,
Total no. of ways = 5$\times$10
When we have to select either a maths book or a physics book, then the no. of ways of selecting any one of the two books would follow addition rule and hence,
Total no. of ways = 5 + 10