Complementary events must have a sum of 1. Which of the following did you include in your response? Check all that apply.

Complementary events must have probabilities that add to 1. Here, P(red) + P(blue) = 3/5, so choosing red and choosing blue are not complements. The red and blue marbles also do not account for all the outcomes, because there are other marbles besides red and blue.

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