Hey there! :D
Add all the candies together.
15+20+10= 45
What is the probability of drawing a red candy?
15/45=.333333 or 33% chance.
A blue candy?
20/45= 0.444444 or 44% chance.
Something besides a yellow candy?
35/45= 0.777777 or 77% chance.
If you added the last two results together 33% and 44%, you would also have 77%.
I hope this helps!
~kaikers