or
A science teacher presented a balloon to his class and posed the question, "If I keep this balloon in the freezer overnight, what will occur?" He followed up with, "Are you confident about your answer?" The teacher recorded his students' responses.
The probability that a student believes the balloon will expand is 0.4, the probability that a student was confident is 0.8, and the probability that a student believes the balloon will expand and was confident is 0.2.
What is the probability that a randomly chosen student believes the balloon will expand or was confident?
Write your answer as a whole number, decimal, or simplified fraction.
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