Answer:
Step-by-step explanation:
Riddle #3
1000's digit is 7 as it is the only prime number over 6
One's digit is 2 as it is the only even prime number.
Ten's digit is half of 100's and the number is divisible by 4
Therefore it should be either 8 & 4 or 6 & 3 or 4 & 2 or 2 & 1
In the case of 8 & 4 and 4 & 2 the number is not divisible by 4
It can't be 1 & 2 as all the digits are different.
So the number is 7632
Riddle #4
Since the number is divisible by 5, One's number should be either 5 or 0
Therefore tens digit should be 8 or 3 as it is 3 more than the one's digit
The number should be 485 as the sum is 17.
