I'll focus on question 10 only. Let me know if you need me to answer the others.
We have the population with this set of numbers: {2,4,6,8,10}
There are 5 values in that set.
Now consider having slots labeled A,B and C to represent the three placeholders for the numbers.
- For slot A, we have 5 choices
- Slot B has 5-1 = 4 choices
- Slot C has 5-2 = 3 choices
There are 5*4*3 = 20*3 = 60 permutations and 60/(3*2*1) = 60/6 = 10 combinations.
Therefore, we have 10 different subsamples of 3 items.
Answer: Choice C) 10