Answer:
To ensure to get five pairs of white socks, I need to pull out at least 11 pairs of socks from my sock drawer.
Step-by-step explanation:
There are 6 pairs of white socks and 6 pairs of black socks mixed up in my sock drawer. If I want to ensure to get five pairs of white socks, I need to pull out at least (6 + 5) = 11 pairs of socks since at most there can be 6 pairs of black socks in my chosen set of socks.