Question 310548
Let's pick red (R) as our color.
First red.
{{{P(R)=10/50=1/5}}}
Skittle is not replaced. 
Second red
{{{P(R)=9/49}}}
Skittle is not replaced. 
Third red
{{{P(R)=8/48=1/6}}}
{{{P(R,R,R)=(1/5)(9/49)(1/6)=3/490}}}