980 = 1,000 - 20
980
20 forties = 800 800 is 200 less than 1000.
There are 1000 millimeters in a meter. There are 1000 meters in a kilometer. Given this information the answer is obvious.
All the prime numbers less than 20 are 2,3,5,7,11,13,17,19
Yes, 2000 meters is less than 20 kilometers. To convert meters to kilometers, you divide by 1000 since there are 1000 meters in a kilometer. Therefore, 2000 meters is equal to 2 kilometers. Comparing 2 kilometers to 20 kilometers, it is clear that 2 kilometers is indeed less than 20 kilometers.
Usually you can't, because it's less than 1. If I HAVE to write it, I would write 013/20.
A more formal definition for a number less than 20 could be, "a number x, x < 20" or if you want to express the set of all numbers less than 20 "{x | x < 20}" which is read "the set of all numbers x such that x is less than 20". In interval notation, you can write (-infinity, 20) where "infinity" should be replaced by the infinity symbol.
20 - 11 = 9
20 grams is less than 2kg. 2kg is 2000 grams.
9999
The prime numbers less than 20 are 2, 3, 5, 7, 11, 13, 17, and 19.
20/1000 = 0.020