Question

Two cards are drawn at random from well shuffled deck of 52 cards. What is the probability that at least one of them is red?

Answer 1

how many red cards are there?

Answer 2

26

Answer 3

so whats the probab. of drawing 1 red card from pack ?

Answer 4

1/1326

Answer 5

probability of atleast 1 = 1- probability of none
= 1- probability of NOT red *NOT red.

Answer 6

how

Answer 7

By enumeration:
Both red, first choice 26 of 52, second choice 25 of 51 = \[\frac{26}{52} * \frac{25}{51} = \frac{26}{2*51}\]
First one or second one red, first choice 26 of 52, second choice 26 of 51 = \[2 * \frac{26}{52} * \frac{26}{51} = \frac{26}{51}\]
Either one red = sum of the above = \[\frac{26}{2*51} + \frac{2*26}{2*51} = \frac{3*26}{2*51}\]

I think.

Answer 8

you have a typo

\[\frac{26}{52} \cdot \frac{25}{51} =\frac{1}{2}\cdot\frac{25}{51}= \frac{25}{2\cdot51}\]