One. And that is 84.
3
As many as you want. You can write any number of additions, subtractions, etc. that result in this number.
If you write every number once, then you will write the number nine exactly once. If you mean "... the digit9, it should appear 20 times: 10 times in the ten's place, and 10 times in the one's place.
You would need infinitely many digits to write all numbers. However, to write all whole number (integers) you would need 4243.
As many as you want.
As many as you want. An unlimited number of ways.
How many languages can you write......? The answer: a lot (depending on the above question)
you can write that answer a thousand million ways!
One. And that is 84.
3
There are three ways you can write the number 10. You can use X, as in Roman numerals, ten, or 10.
As many as you want. You can write any number of additions, subtractions, etc. that result in this number.
If you write every number once, then you will write the number nine exactly once. If you mean "... the digit9, it should appear 20 times: 10 times in the ten's place, and 10 times in the one's place.
111 is the answer
An infinite number.
Count how many parts there are in total (both shaded and unshaded) and write this as the denominator (bottom number) of the fraction. Count how many shaded parts there are and write this as the numerator (top number) of the fraction. You now have the fraction of the whole that is shaded.