find the minimum and maximum number of digits in the sum of any two 4 digit numbers

The largest four digit number is 9999, and thus, a maximum value can be obtained by adding 9999 and 9999, and the resultant number will be having the maximum number of digits.

9999+9999=19998$9999+9999=19998$

Therefore, the maximum number of digits of the resultant number, when two four-digit numbers are added is 5.

Let us now discuss the minimum:

The smallest four digit number is 1000, and thus, a minimum value can be obtained by adding 1000 and 1000, and the resultant number will be having the minimum number of digits.

1000+1000=2000$1000+1000=2000$

Therefore, the minimum number of digits of the resultant number, when two four-digit numbers are added is 4.


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