Question 958165
Red dot balls : {7,14,21,28,35,42,49} - 7 members
Multiples of 5 balls : {5,10,15,20,25,30,35,40,45,50} - 10 members
Both red dot and multiple of 5 : {35}
So then,
{{{P=(7+10-1)/50}}}
{{{P=16/50}}}
{{{P=8/25}}}