I am an even 3-digit number. If you round me to the nearest ten, I become 200. The sum of my digits is 18. What number am I?
Answer is 198 All possible values are ......192,194,196,198,200,202,204,206.............. And the nearest value is 198, whose sum of digits is 1+9+8 = 18
I am thinking of a two-digit number.
If I write 3 to the left of my number, and double this three-digit number, the result is 27 times my original number.
What is my number?
I'm a 5 digit number, the first and last digits are the same and add up to an even number. Multiply that number by its self and the number is under 10 and odd. That will be the fourth number. Subtract five from it and it will be the second number. Divide it in half and that is my third number.
What am I?
There's a three digit number which: If you add seven to it it divides exactly by seven; If you add eight to it it divides exactly by eight; If you add nine to it it divides exactly by nine. What is the number?