Answer:
Step-by-step explanation:
1. Number of peoples available to choose from = 20
\(\text{Ways of selecting the captain from 20 people = }_{1}^{20}\textrm {C}=20\)
After selecting the captain number of people left among which co captain can be selected = 20 - 1 = 19
\(\text{Ways of selecting the co captain from 19 people = }_{1}^{19}\textrm {C}=19\)
Hence, Number of ways a coach select the captain and co-captain of a team from a group of 20 people = 20 × 19 = 380
Therefore, The correct option is C. 380
2. Total number of players = 7
Number of players to be selected = 5
\(\text{So, number of ways of selecting 5 players out of 7 = }_{5}^{7}\textrm {C}=21\)
Therefore, The correct option is A. 21
3. Total number of outcomes = 20
The digits 1, 2, 3, 4, 5, 6 represent the student who make a C
Number of students who make a C at least 3 times = 13
\(\bf\textbf{Required Probability = }\frac{13}{20}\)
Therefore, The correct option is D
