Answer:
Greatest = 699,999
Least = 600,900
Explanation:
6 digit numbers
9 in the Hundred place
3 fewer hundred thousands than hundred
9 - 3 = 6
Hundred thousand = 600,000
Hence, greatest 6 digit number
Hth__TTh__Th__H__T__U
6____9____9___9__9__9
600,000 + 90,000 + 9,000 + 900 + 90 + 9
= 699,999
Hence, least 6 digit number
Hth__TTh__Th__H__T__U
6____0____0___9__0__0
600,000 + 00000 + 0000 + 900 + 00 + 0
= 600,900