Ages 11–13🧮 Mathematics10 verified questions on this shelf

Complementary events

Understand and apply the rule that probabilities of all mutually exclusive outcomes sum to one; use this to find the probability of a complementary event (P(not A) = 1 − P(A))

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Question 1 of 3

A spinner is divided into five regions named W, X, Y, Z, and V. The teacher writes the following probabilities for landing on each region: P(W) = 1/4, P(X) = 0.2, P(Y) = 3/10, P(Z) = 0.15. What probability must be assigned to region V so that the probabilities for all five regions add up to 1?

Question 2 of 3

A spinner is divided into four sections. The teacher writes the following probabilities for landing on each section: P(A) = 0.25, P(B) = 0.30, P(C) = 0.20, P(D) = 0.25. Do these probabilities form a valid probability distribution for the spinner?

Question 3 of 3

A fair six‑sided die is rolled once. What is the probability of obtaining an even number?

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