4600
122 to the nearest 100 is 100
The least number is 4550; the greatest is 4650 and I have no idea what a phone number has to do with any of this.
103 to the nearest hundreds is 100
100
100
4198 to the nearest 100 = 4200
That is 4800
100
100
75 rounded to the nearest 100 is 100.
100