Face 1 2 3 4 5 6
Frequency 12 18 y 30 2y 45
Given the table above as the results of tossing a fair die 150 times. Find the probability of obtaining a 5.
  • A \(\frac{1}{10}\)
  • B \(\frac{1}{6}\)
  • C \(\frac{1}{5}\)
  • D \(\frac{3}{10}\)
waec 2017furthermathematics

The correct answer is C. \(\frac{1}{5}\)

Probability of obtaining a 5 = \(\frac{\text{frequency of 5}}{\text{total frequency}}\)

\(12+18+y+30+2y+45 = 150 \implies 105+3y = 150\)

\(3y = 45; y = 15\)

Probability of 5 = \(\frac{2\times 15}{150} = \frac{1}{5}\)

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