A bag contains red, blue and green counters only. The probability of selecting a red counter is 0.3 and the probability of selecting a blue counter is 0.45. What is the probability of selecting a green counter?

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Question

A bag contains red, blue and green counters only. The probability of selecting a red counter is 0.3 and the probability of selecting a blue counter is 0.45. What is the probability of selecting a green counter?

Accepted Answer

0.25 — 25. Award 1 mark for calculating 1 - 0.3 - 0.45 = 0.25. A is incorrect — subtracts only one probability from 1. C is incorrect — this adds the two given probabilities instead of subtracting from 1. D is incorrect — this adds the two probabilities together.

Answer

0.75

Answer

0.35

Answer

0.15

Answer

0.25

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