1000 x 3 = 3000
1000 times 3 is 3000. Multiplying by 1000 adds three zeros, and it is also plain repeated addition: three thousands. The same sum sits underneath most metric unit conversions.
1,000 × 3 = 3,000
Adding 1,000 to itself 3 times gives the same answer.
Three thousands
Multiplying by 1000 puts three zeros after the digit, so 3 becomes 3000. The long way is repeated addition: 1000 + 1000 + 1000 = 3000. With a factor as small as 3 that is usually finished before you reach the end of the question.
This is the metric conversion sum
A thousand is the step between metric units, so this calculation is doing a conversion whether you meant it to or not:
- 3 kilograms is 3000 grams
- 3 kilometres is 3000 metres
- 3 litres is 3000 millilitres
- 3 seconds is 3000 milliseconds
Every one of those is 1000 x 3 with a unit label attached. If you can do the sum you can do the conversion, in either direction — dividing 3000 by 1000 takes the three zeros back off.
The number 3000
3000 factors as 2 x 2 x 2 x 3 x 5 x 5 x 5. Its digits add to 3, so it divides by 3 but not by 9. Half of it is 1500 and a third of it is 1000, back where we started.
Same answer, different question
30 x 100 also comes to 3000 — the same three zeros, split differently between the two numbers. 100 x 3 is 300, one tenth of this, and it is the pair most often confused with it. One step up is 1000 x 4 = 4000.