# What is the least number of balls to be picked from a bag of 64 balls (eight of each color) to select 3 red balls?

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A bag contains 64 balls of eight different colours. There are eight of each colour (including red). What is the least number you would have to pick, without looking, to be sure of selecting 3 red balls?

posted Sep 10, 2015

–1 vote

59 balls.
To be sure you must have all the balls which are not red and 3 balls which are red => 7 * 8 + 3 = 59 balls

answer Sep 10, 2015 by

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