The two-digit number____ 1 is divisible by 9.
fill in the blank with the number
The two-digit number 18 is divisible by 9.
To find a two-digit number that is divisible by 9, we need to identify a number between 10 and 99 that meets this condition.
We know that a number is divisible by 9 if the sum of its digits is divisible by 9. Therefore, we need to find a two-digit number where the sum of its digits equals 9.
Starting with the largest possible digit, which is 9, we can see that it is not possible to find a two-digit number that fits this criteria, as 9 itself is not divisible by 9.
Next, we move to 8. If we choose 89, the sum of the digits is 8 + 9 = 17, which is not divisible by 9.
Continuing this process, we find that no two-digit number with a leading digit of 7, 6, 5, 4, 3, 2, or 1 is divisible by 9 when considering the sum of its digits.
Finally, we reach the digit 0. If we choose 90, the sum of the digits is 9 + 0 = 9, which is divisible by 9.
Therefore, the two-digit number that is divisible by 9 is 90.