what did I do wrong?
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Answer:
19/100
Step-by-step explanation:
probability= number of cards that have digit 3/ total number of cards
all numbers from 30-39 have the digit 3
as well as 3, 13, 23, 43, 53, 63, 73, 83, 93
so 10 instances in between 30-39 and 9 listed above,
10+9=19 and 19/100