A number has two zeros, and the sum of digits is 4. What are the maximum and minimum values of this number?

A number has two zeros, and the sum of the digits on other non-zero digits is 4, ①.

To maximize this number, you need as many digits as possible, so1+1+1+1= 4, and then rank both zeros to the lowest place. The maximum is111100.

(2) The minimum number refers to the least number of digits. Direct 1 digit is 4, and the smallest number is 400.