100000000000 kantutan
More than one
Assuming leading zeros are not permitted, then: If repeats are not allowed there are 30 possible numbers. If repeats are allowed there are 60 possible numbers.
6*6*3 = 108 numbers.
24 of them. So we have a 2 or 6 in the unit position, therefore (2)(4)(3) = 24 even three-digit numbers, can be formed.
You can not add two positive prime numbers and get zero.
There are 504 such numbers.
100,000
Assuming that leading zeros are not permitted (that is the lowest ten digit number is 1 000 000 000), then there are 4 500 000 000 possible even numbers
9999
The question to help my son with his homework is: How many unique numbers can be formed by combining three sets of three digital decimal numbers
18
How many even numbers are there between 165 and 345