Use a 1 - 7 digit number that can be rounded to 6300000

1. There will a lot but I am just going to show some of the possible answers:

we are going to use numbers from 1 to 7 and rounded it to 6 300 000.

The given number has 7 digits and numbers from 1 to 7 also have 7 digits

=> 1 2 3 4 5 6 7 (now, arrange to get the correct answer)

=> 6 321 457, since the number next to 3 is lower than 5, then rounding down will apply

=> 6 300 000

Another example:

=> 6 275 341, since the number next to 2 is higher than 5, which is 7, rounding up will apply

=> 6 300 000