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Hexadecimal Colors

Quiz Question.

Hexadecimal colors are represented by a pound sign followed by a series of letters and numbers. like this: #RRGGBB or #RGB

Which of these is Not a hexadecimal color?

A. FF0000

B. 9972GL

C. 000000


3 Answers

Haider Ali
.a{fill-rule:evenodd;}techdegree seal-36
Haider Ali
Python Development Techdegree Graduate 24,724 Points

Hi there Jason. The counting system we use in our everyday lives is base 10 also known as decimal. It includes the numbers 0, 1, 2, 3, 4, 5, 6, 7, 8, 9. Hexadecimal is base 16. However, you may be thinking there are only 10 numbers and Hexadecimal uses 16. Well, after 9, the first 6 letters of the alphabet are used to represent 10, 11, 12, 13, 14, 15. so these are all the units that hexadecimal uses:

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F.

These are the only units that hexadecimal uses so the one which is not hexadecimal would be B as it includes the letter L which is not a part of hexadecimal. If you have not learnt about hexadecimal before, this may seem slightly confusing but you should get used to it :)

Thanks, Haider

Kristian Gausel
Kristian Gausel
14,661 Points

Don't be confused about the #RRGGBB part of the question. Hex only has the letters A-F where A is 10, B is 11, C is 12 and so on.

Thank you, everyone for responding to my question about hexadecimal colors.

Tobias Helmrich
Tobias Helmrich
31,602 Points

Hey there,

the right answer is "B. 9972GL" because hex values only go up until "F". So "G" and "L" are invalid.

I hope that helps! :)