1000 x 20 = 20000
1000 times 20 is 20000. Count the zeros: three in 1000, one in 20, so the 2 carries four zeros. Below is the working, a calculator, and the neighbouring answers.
1,000 × 20 = 20,000
Adding 1,000 to itself 20 times gives the same answer.
The working
Split the 20 into 2 x 10. First 1000 x 2 = 2000, then 2000 x 10 = 20000. Or count zeros instead: 1 x 2 = 2, and 1000 brings three zeros while 20 brings one, so the answer is a 2 followed by four zeros. 20000.
Multiplying by 1000 is the metric step
A thousand is the gap between one metric unit and the next one down: 1000 millimetres in a metre, 1000 grams in a kilogram, 1000 millilitres in a litre, 1000 metres in a kilometre. So this one calculation converts all of them.
- 20 metres = 20000 millimetres
- 20 kilograms = 20000 grams
- 20 litres = 20000 millilitres
- 20 kilometres = 20000 metres
Watch the zero count
1000 x 20 = 20000, but 1000 x 200 = 200000. One extra zero on the input puts one extra zero on the answer, and at this size the two are easy to misread. Reverse it to check: 20000 divided by 1000 = 20.
Other pairs that reach 20000
The product does not care how the factors are split. 200 x 100 gives the same 20000, and so do 2000 x 10, 4000 x 5 and 500 x 40. Nearby on the ladder are 1000 x 2 = 2000 and 10000 x 20 = 200000.