Question

I’m a 4-digit number. My 1st 2 digits from the left are divisible by 5. My 3rd and 4th digits from the left are divisible by 9. The sum of my digits is 18. Each of my digit is different. I’m divisible by 4. I’m less than 6000. My units digit is twice my tens digit.

Answer 1

just start fitting in the facts.

1st 2 divisible by 5 means they end in 0 or 5

last 2 divisible by 9 and all different means not 09,45,54 or 90

units = twice tens means they are 36
so, the number is xx36.

That means the first two digits also add to 9, which means the number is

4536 or 9036

But the number is less than 5000, so it must be 4536.