- Determine the two consecutive multiples of 1,000 that bracket 42,123
- 42,123 is between 42,000 and 43,000
- 42,500 is the midpoint between 42,000 and 43,000
- As illustrated on the number line, 42,123 is less than the midpoint (42,500)
- Therefore, 42,123 rounded to the nearest thousand = 42,000
