In this case, we'll have to carry out several steps to find the solution.
Step 01:
Data
6 red gumballs
3 green gumballs
5 blue gumballs
probability red gumball = ?
Step 02:
total gumballs = 6 + 3 + 5 = 14
probability red gumball = red gumballs / total gumballs
probability red gumball = 6 / 14 = 3 / 7
The answer is:
probability red gumball = 3 / 7