I take this question to mean what number when added to 457 will yield 999. In this case it is 542.
999
956
245
ⓉⒽⒺ 🅐🅝🅢🅦🅔🅡 ⒾⓈ 542
96475
don't know
There is no such number. You can add 456000 or 456878322168000 or even 1581687671173873681773618733111
It is 634. 9-3 = 6 9-6 = 3 9-5 = 4 365 +634 =999 No regrouping required.
6 times
Any number. Not everyone needs to regroup.
96475
don't know
100
634
There is no such number. You can add 456000 or 456878322168000 or even 1581687671173873681773618733111
460
It is 634. 9-3 = 6 9-6 = 3 9-5 = 4 365 +634 =999 No regrouping required.
6 times
-423
2
4