Answer:
It depends on the person, everybody snorts a different amount.
Basically, some people can snort cocaine off a coin or from the top of their hand, which is normally only about 0.05 grams, or even less.
Some people can cut a gram into about 5-10 lines, which means they will be snorting about 0.1 to 0.2 grams per line.
However, with some people they need to snort about 0.5 grams per line before cocaine affect them.
A gram of cocaine = £30 ($48) to £50 ($80), so depending on who you are, cocaine can work out cheap or be pretty expensive for you.