Question 974945
Edwin is incorrect.
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You didn't say if odd an even numbers had to alternate - he didn't solve for that.
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Edwin is actually my mother-in-law.
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How many ways to make a 3 digit number by using numbers 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
That is divisible by 10
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The 1's digit has to be zero.
If, eg, 010 is not considered to be a 3 digit #, then the 1st digit cannot be zero.
--> 9*10*1 = 90 ways.