OCR Further Discrete 2022 June — Question 3

Exam BoardOCR
ModuleFurther Discrete (Further Discrete)
Year2022
SessionJune
TopicCombinations & Selection

3 A para relay team of 4 swimmers needs to be chosen from a group of 7 swimmers.
  1. How many ways are there to choose 4 swimmers from 7? There are no restrictions on how many men and how many women are in the team. The group of 7 swimmers consists of 5 men and 2 women.
  2. How many ways are there to choose a team with more men than women? The physical impairment of each swimmer is given a score.
    The scores for the swimmers are
    \(\begin{array} { l l l l l l l } 3 & 4 & 4 & 6 & 7 & 8 & 9 \end{array}\) The total score for the team must be 20 or less.
  3. How many different valid teams are possible? The order of the swimmers in the team is now taken into consideration.
  4. In total, how many different arrangements are there of valid teams?
  5. In how many of these valid teams are the scores of the swimmers in increasing order? For example, 3, 4, 4, 8 but not 4, 3, 4, 8 .