add more detail to answers

Author: Liam310

number-systems/Part-2.md

@@ -13,10 +13,10 @@ Q17: If reading the byte 0x21 as an ASCII character, what character would it mea
 Answer: ! (exclamation point character corresponds to hex code 21)
 
 Q18: If reading the byte 0x21 as a greyscale colour, as described in "Approaches for Representing Colors and Images", what colour would it mean?
-Answer: Very dark grey
+Answer: Very dark grey - the scale goes from 0x00 (black) to 0xFF (white), and 0x21 is very low down on this scale, thus resulting in a colour close to black
 
 Q19: If reading the bytes 0xAA00FF as a sequence of three one-byte decimal numbers, what decimal numbers would they be?
 Answer: AA is 170, 00 is 0, FF is 255
 
 Q20: If reading the bytes 0xAA00FF as an RGB colour, as described in "Approaches for Representing Colors and Images", what colour would it mean?
-Answer: Purple
+Answer: Purple - AA is darkish red, 00 is no green, FF is max blue, and red and blue mix to make purple