Subject: check secondary worksheet I was wondering if you could let me know if I did these problems correctly, and if not can you let me know how to fix them, thanks Dee. A card is selected from an ordinary deck of cards. What is the probability of. . . selecting 2 aces in a row? i got .036038961 and If you toss two dice, what would be your probability of the following? a sum of six - I got 5/36  a sum of 9 or greater - I got 7/36  a sum of four 3 times in a row - I got 1/729  an even sum - I got 9/36 thanks Hi Dee, The answer to the first question depends on how you draw the two cards. If you are selecting one card from a standard deck the probability of it being an ace is 4/52 = 1/13. If you got an ace and then select a second card the probability that it is an ace is 3/51. (There are only 51 cards left and only 3 aces.) Thus the probability that both are aces is 1/13 x 3/51. If you are to put the first ace back in the deck before you draw the second card then the probability that the second card is an ace is also 4/52. In this case the probability of two aces is (4/52)2. For the dice problem you should make a 6 by 6 chart of all the 36 possibilities of the result of tossing two dice, think of them as Red and Green. ``` 1 2 3 4 5 6 1 (1,1) (1,2) (1,3) (1,4) (1,5) (1,6) 2 (2,1) (2,2) (2,3) (2,4) (2,5) (2,6) 3 (3,1) (3,2) (3,3) (3,4) (3,5) (3,6) . . . . . . . . . . . . . . ``` Looking at the table above I also got 5/36 for the first part. You can get a sum of six from (5,1), (4,2) (3,3), (2,4) and (1,5). Now can you do the rest? Penny Go to Math Central