5 Salah decides to attempt the crossword puzzle in his newspaper each day. The probability that he will complete the puzzle on any given day is 0.65 , independent of other days.
[0pt]
- Find the probability that Salah completes the puzzle for the first time on the 5th day. [1]
- Find the probability that Salah completes the puzzle for the second time on the 5th day.
- Find the probability that Salah completes the puzzle fewer than 5 times in a week (7 days). [3]
\includegraphics[max width=\textwidth, alt={}, center]{9b21cc0f-b043-4251-8aa9-cb1e5c2fb5d0-10_2713_31_145_2014} - Use a suitable approximation to find the probability that Salah completes the puzzle more than 50 times in a period of 84 days.