Question

1. Compute the number of ways you can select n elements from N elements for each of the following:

   1. N=9, n=4

   2. N=9, n=5

   3. N=8, n=4

   4. N=8, n=5

   5. Use the results of a, b, c, and d to verify the properties of combinations

Answer 1

Solution:

Number of ways of selecting n elements from N elements is given by,

1) We have, N = 9 , n = 4

Hence, number of ways of selecting 4 elements from 9 elements is 126.

2) We have, N = 9 and n = 5

Hence, number of ways of selecting 5 elements from 9 elements is 126.

3) We have, N = 8 , n = 4

Hence, number of ways of selecting 4 elements from 8 elements is 70.

4) We have, N = 8 , n = 5

Hence, number of ways of selecting 5 elements from 8 elements is 56.