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Probability, SM-Bank 088

A spinner with equal divisions has the numbers 1, 2 and 3 printed on it.

The probability of spinning the number 2 is \(\dfrac{1}{5}\) and the probability of spinning the number 3 is \(\dfrac{2}{3}\).

What is the probability of spinning the number 1?  (2 marks)

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\(\dfrac{2}{15}\)

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\(\text{The sum of all probabilities in an event = 1}\)

\(P\text{(1)}\) \(=1-\Bigg(\dfrac{1}{5}+\dfrac{2}{3}\Bigg)\)
  \(=1-\Bigg(\dfrac{3}{15}+\dfrac{10}{15}\Bigg)\)
  \(=1-\dfrac{13}{15}=\dfrac{2}{15}\)