CBSE · Class 6-12

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Class 10 · Mathematics (Basic) · Unit 14: Probability

Complementary Events

Lesson 3 of 6

\bar E

(complement of

E

) is the event that

E

does not occur.

P(E) + P(\bar E) = 1

, so

P(\bar E) = 1 - P(E)

. Complements often simplify: 'at least one head in 3 tosses' is easier as

1 - P(\text{no heads})

.

Event and Favourable Outcomes

All lessons in this unit