508,002 views
13 votes
13 votes
A box contains 6 red, 3 white, 2 green, and 1 black (total 12) identical balls. What is the least number of balls nevessary to take out randomly ( without looking) to be sure getting, atleast one red ball?

User Dor Dadush
by
2.9k points

1 Answer

14 votes
14 votes

Answer:

7 balls

Explanation:

Look for the worst case scenario:

Get 3 white, 2 green, and 1 black.

That adds up to: 3 + 2 + 1 = 6.

+1 red ball: 6 + 1 =7

7 balls

User Hatchet
by
2.7k points
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