Answer:
1/5525 ≈ 0.018%
Step-by-step explanation:
There are 4 kings in a standard deck of 52 cards.
The probability that the first card is a king is 4/52.
The probability that the second card is also a king is 3/51 (the first king isn't replaced, so there's one less king and one less card in the deck).
The probability that the third card is a king is 2/50.
The probability of choosing 3 king cards is therefore:
P = (4/52) (3/51) (2/50)
P = (1/13) (1/17) (1/25)
P = 1/5525
P ≈ 0.018%
z = 60
100+20+z=180
120+z=180
z=60
