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Vernon
04-23-2008, 12:10 PM
Heya , just wondering if I could get some second thoughts on a couple of things.

The question " A standard pack of cards is shuffled. You then deal three cards in a row. Let A be the event that the left card is a heart, Let B be the event that exactly two of the three cards are jacks"

Find P(A) and P(B)

It's an easy question but would just like to check my workings as the rest of the question relies on these answers.

Would I be right in assuming that the 1st card is the left card , middle 2nd and right 3rd?

If going on this assumption then;

P(A) = \frac{1}{4}

and for P(B) there are 3 different possibilities i.e

JJ-
J-J and
-JJ where - represents any card not a jack

so P(B) would equal \frac{1}{13} \times \frac{3}{51} \times \frac{48}{50} multiplied by 3 because of there being 3 different possibilities.

So P(B) = \frac{72}{5525} = 0.0130

Would this be correct ?

Any help would be great thanks :)

royhaas
04-23-2008, 01:04 PM
Your calculations are correct.

Vernon
04-23-2008, 04:01 PM
Great thanks :)