[ Homework Help ] Open Question : Data Management Questions i cant understand?

1.) A security code used to consist of 2 odd digits followed by 4 even digits. To allow more codes, to be generated, a new system uses 2 even digits followed by any 3 digits. What is the increase in the number of possible codes 2.) Lotto 7-45 has 45 numbers you can choose from, and you must pick 7. If a free ticket is given out by matching 2 correct numbers, what is the probability of getting this particular prize? 3.)There are 7 accountants and 4 marketing agents at a conference. Find probability of three different door prizes being awarded to all accountants or all marketing agents. 4.) At a family gathering, 3 different door prizes are given away. There are tables with specific age groups. There are 5 children at one table, 8 teenagers at another, 15 adults, and 9 seniors. Find the probability of: a) only seniors win the prize b) all three prizes goes to the children c) at least one prize goes to the children 5 a) a standard deck of cards is shuffled and three cards are selected. What is the probability that the third card is either a red face card or king if the king of diamonds and the king of spades are selected as the first two cards? b) Does this probability change if the first two cards selected are the queen of diamonds and the king of spades? Explain 6.) If nPr =6720 and nCr = 56, what is the value of r? without using trial and error... I REALLY DONT KNOW HOW TO DO THESE QUESTIONS :(

Source: http://answers.yahoo.com/question/index?qid=20110320135925AAJ878H

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