The probabilities that John and James pass an examination are \(\frac {3}{4}\)and \(\frac {3}{5}\) respectively. Find the probability of both boys failing the examination.
A. \(\frac {1}{10}\) B. \(\frac {2}{10}\) C. \(\frac {9}{20}\) D. \(\frac {11}{20}\)
Correct Answer: D
Explanation
Pr(both John and James passed)  = \(\frac {3}{4}\) x \(\frac {3}{5}\)  = \(\frac {9}{20}\)  Pr(john and james failed)= 1- Pr(john and james passed)  = 1 – \(\frac {9}{20}\)  = \(\frac {11}{20}\)  Answer is D
