It rounds up to 1000 because 600 is greater than 500
To round to the nearest thousand, the two numbers in their thousands, on either side of 18627 are:18000 which is at a distance of 18627 - 18000 = 627, and19000 which is at a distance of 19000 - 18627 = 373.The smaller of these is 373 and so the nearest 1000 is 19000.
600
630
0.627 = 627/1000
627/1000
600
1000
1000
1000
1000
1000
736 to the nearest 1000 is 1000. When rounding to the nearest 1000, you look at the hundreds place of the number in question. Since the hundreds place in 736 is less than 500, you round down to the nearest 1000, which is 1000.