All you need to know is the amount of glazed doughnuts and chocolate doughnuts, the total number of doughnuts. The amount of jelly doughnuts is just used to add the total amount, so you can say there are 12 doughnuts. Of the 12 doughnuts there are 3 glazed doughnuts and 5 chocolate doughnuts. Getting either a glazed doughnut or a chocolate doughnut is mutually exclusive, which means they cannot occur at the same time.

There is a rule in probability when dealing with mutually exclusive events (you know it's mutually exclusive because it says, "either or"), you simply add the two events together, and divide by the total.

3 Glazed Doughnuts = 5 Chocolate Doughnuts = 8 Doughnuts You Could Pick Up

So, (3/12) +(5/12) = 8/12

8/12 = 2/3

2/3 approximately equals 66%

So, you have a 2 out of 3 chance of getting either a glazed doughnut or chocolate doughnut.

Therefore you have approximately a 66% chance of either glazed or chocolate.

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