Question 1169499
how many three digit numbers can be formed from the set 0-9 if repetition are allowed and the number must be 
a)even
--> the 1's digit must be 0, 2, 4, 6 or 8
Units is 1 of 5
Tens is 1 of 10
Hundreds is 1 of 10
---> 5*10*10
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b)divisible by 5
---> Units is 5 or 0
Tens is 1 of 10
Hundreds is 1 of 10
---> 2*10*10
======================
c)divisible by 10
---> Units is 0
Tens is 1 of 10
Hundreds is 1 of 10
---> 10*10
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All assuming leading zero is acceptable, eg, 012.
If not, you need to specify that.