Question

What is the total number of ways of selecting at least one ring from 2 sets of 10 identical rings?

• A. 100
• B. 120
• C. 119
• D. 121

Answer 1

The correct option is B 120

If all rings are identical, then number of ways is 11.
Since there are 2 sets, there are 11 $\times$ 11=121 ways
Since atleast 1 has to selected, number of ways = 121 - 1 = 120 ways.