On the first draw, there are 10 numerals out of 36 cards.
P(first card is a number) = 10/36 = 5/18
On the second draw, there are 9 numerals out of 35 cards.
P(second card is a number) = 9/35
The probability of both events is the product:
P(both cards are numbers) = P(first card is a number) x P(second card is a number)
= 5/18 x 9/35
= 1/2 x 1/7 (cancel a 5 and a 9).
= 1/14