Answer: 3/5
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Step-by-step explanation:
The set {1, 2}U{2, 6, 7, 9}U{5, 6, 7} simplifies to {1,2,5,6,7,9} after we combine everything and sort the values. We toss any duplicates.
Let B = {1,2,5,6,7,9}
There are 6 items in set B out of 10 items in set A.
The probability of landing in set B, if you pick something randomly from A, is 6/10 = 3/5