7/25, 6/25, and 11/50. Looks like they are already in order, or you meant to do that...
Answer to 1: 648
Answer to 2: 175
Answer: 
Step-by-step explanation:
Give expression is,

Since L.C.M ( 12, 8 ) = 24





The probability that the first two votes drawn are both for candidate a is given by:
3C2/5C2 = 3/10
Having drawn two votes for candidate a on the first two draws, there are 2 votes for candidate b and one vote for candidate a remaining. The probability that a vote for candidate b will be drawn on the third draw is:
2/3.
After the first three draws, there reains one vote for candidate a and one vote for candidate b. The probability that a vote for candidate a will be drawn on the fourth draw is:
1/2.
The probability of the ordering aabab is therefore given by:

The answer is: 0.1.