SOLUTION: A child has nine cards numbered 1 through 9. The child places three cards in a row to form a three-digit number. Find the probability that the number is larger than 600?

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Question 715814: A child has nine cards numbered 1 through 9. The child places three cards in a row to form a three-digit number. Find the probability that the number is larger than 600?
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
The numerator of the probability is the number of ways she can
succeed in picking a number greater than 600.

There are 4 ways she can pick the first digit as 6,7,8, or 9
That leaves 8 ways she can pick the second digit.
That leaves 7 ways she can pick the third digit.

So there are 4򊤋 ways she can pick a number larger than 600.

The denominator of the probability is the number of ways she can
pick any number whether smaller or larger than 600.

There are 9 way she can pick the first digit.
That leaves 8 ways she can pick the second digit.
That leaves 7 ways she can pick the third digit.
 
So there are 9򊤋 ways she can pick any nunber (whether smaller 
or larger than 600).

So the probability that she will succeed in picking a number greater
than 600 is the fraction

     %284%2A8%2A7%29%2F%289%2A8%2A7%29 = %284%2Across%288%29%2Across%287%29%29%2F%289%2Across%288%29%2Across%287%29%29 = 4%2F9

Edwin