It has to be a multiple of 5. All multiples of 5 either
end in 0 or 5. Since it has to be even it has to end in 0,
since if it ended in 5 it would be odd.
Therefore the answer to this
a. what is the digit in the ones place?
must be 0, because the digit on the right end of the number is the
ones digit.
b. what can the number be?
Since it ends with a zero it is divisible by 10. So if you divide
it by 10, the quotient will be a 2-digit number which is the same
as the number without the 0 on the right end.
But the quotient will still be divisible by 3.
So the number could be any two digit number that is a
multiple of 3 with a 0 on the right end of it for its ones digit.
The smallest 2-digit number that is a multiple of 3 is 12, so the
smallest the number could be is 120.
The largest 2-digit number that is a multiple of 3 is 99, so the
largest the number could be is 990.
So it could be any of these thirty 3-digit numbers:
120, 150, 180, 210, 240, 270, 300, 330, 360, 390,
420, 450, 480, 510, 540, 570, 600, 630, 660, 690,
720, 750, 780, 810, 840, 870, 900, 930, 960, 990.
Edwin
