Answer:
see below
Explanation:
1 2 3 4 5 6 7 8 9 10 = 10 cards
9 of them have 1 digit on them ( 10 has 2 digits)
P( 1 digit) = number with 1 digit) / total = 9/10
P( not have 1 digit)= number not with 1 digit) / total = 1/10
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