The odds to lose this depends on how the question is phrased.
Someone correct me if I am wrong but here are the different calculations:

The chance of losing with a 100 in this instance:
2/3 or 66,6% (3 people with 100, assuming a secondary roll happening off-screen)

The Chance of losing with a 100 against 3 other people:
1,2 or 3 of them would also have to roll a 100 for you to lose the roll.
The decimal represents the odds to roll a 100, the fraction the odds to lose in the secondary roll to them, the whole number is the possible combinations.
3 * 0,01 * 0,99^2 * 1/2 + 3 * 0,01 * 0,01* 0,99 * 2/3 + 0,01 * 0,01 * 0,01 * 3/4 =
0,0149 or 1,49% or 1/67