Numbers written as words: one, three five, ten, twenty-seven Numbers written as numerals: 1, 3, 5, 10, 27
Qualitative
Written form means you have to write your answer in words, not numerals: ten, not 10.
No there actually more combinations that we can make with numbers than letters. That's not actually true, since there are more letters than numerals, but every combination of numerals is a number and there are an infinite number of them, whereas, not all combinations of letters actually make words--there is only a finite number of words.
In numerals : 1,150,000,000,000 In words: one trillion, one hundred fifty billion
Most people prefer to write numbers using digits since this is far shorter than writing out the relevant words.
If writing by hand - count the number of words on one line - then multiply the number of lines by that first number. If using a computer - most word-processing programs have a word-count function in them.
italics
If the number is below ten, then you would use words to represent the numbers, when they are above ten, you use the number (:
Roman numerals represent numbers, they do not represent words.
a straight or curved continuous extent of length without breadth.
In terms of writing style, it looks and sounds better to use either all numerals or all words, so it is either 7700 or it is seventy seven hundred. Mixing numerals and words is a bit awkward.