Fill in the blanks:
The difference between the smallest number of four digits and the largest number of three digits = ……….….. \[ - \] …………… \[ = \] …………..

Hint:
Here, we will first find the value of the largest three digit number and then we will find the value of the smallest four digit number. Then we will subtract these two values to get the required difference between them.

Complete step by step solution:
We will first find the value of the largest three digit number. We know that the largest three digit number is formed by the largest digit among digits 0 to 9.
The largest three digit number is equal to \[999\].
Now, we will find the value of the smallest four digit number. We know that the smallest four digit number is formed by the smallest digit among digits 0 to 9 but remember we can’t take 0 at the first place.
The smallest four digit number \[ = 1000\]
Now, we will subtract the largest three digit number from smallest four digit number.
Required difference between them \[ = 1000 - 999 = 1\].

Hence, the required difference between the smallest four digit number and the largest three digit number is equal to 1.

Note:
Here we need to keep in mind that when we add 1 to the largest three digit number, the number which we will get will be the smallest four digit number. Similarly, when we subtract 1 from the smallest four digit number the number which we will get will be the largest three digit number. Here we can make mistakes by taking the smallest four digit as 9999 and largest three digit as 100. This will be wrong because 9999 is the largest four digit number and 100 is the smallest three digit number. So, we need to be careful while writing the numbers.