I'm not an economist... but at least I know that about myself.
http://www.frbsf.org/economic-research/publications/economic...
I'm glad you "guess" it's nearly 100%. This article (the top Google hit for "effects of minimum wage on employment") suggests it's in the realm of 10% (though it's probably smaller) based on simple linear models of price elasticity. A 10% drop in employment is not nothing! It could absolutely matter! But that's the foundation for a debate, not some made- up numbers.
My main point is that it's foolish to 'guess' and start applying numbers... it's tempting to make a point that's grounded in political philosophy, and slap a coat of speculative, pseudo-quantitative paint on it so it sounds more considered.
To your other point, about not wasting time on internet comments, I will respectfully concede.
1. The group of low-wage workers produce on average $9/hr.
2. A minimum wage of $15/hr is introduced.
3. The income of 10% of the group falls to $0/hr because they lose their jobs, a fall of $9/hr * 0.1 = $0.9/hr on average.
4. The income of 90% of the group rises to the new minimum wage of $15/hr, an increase of $(15 - 9 = 6)/hr * 0.9 = $5.4/hr on average.
5. The net change in income is $(5.4 - 0.9 = 4.5)/hr on average.
So with all these contrived numbers the introduction of the minimum wage raised low-wage worker pay by $4.5/hr on average. Is that bad for low-wage workers?
Of course, really, we should just take ryandamm's advice here [0] and stop trying to provide our arguments with the air of rigour by throwing some made up numbers around.