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The only way we get an odd by multplying two numbers is if each of those two numbers are odd.
From 0 to 9 we have 5 odds. So the number of odd pairs is C(5,2)=10

The only way we get an odd by multplying two numbers is if each of those two numbers are odd. From 0 to 9 we have 5 odds. So the number of odd pairs is C(5,2)=10

So the answer would be 30/40

Martin,

The prob. that the first # can be odd is 5/10 and the prob that the second # is 4/9

So the prob that their product is odd = 5/10 * 4/9 = 2/9

so the prob that the product# is even = 1 - 2/9 =7/9

wow. even though i am exremely embarrased i feel thankful that i do know that 0 is even. goes to show how a simple fact like this could have been the end of me.