# probability

#### deevicsm

##### New member
Here is the homework question - Jar containing 3red 7 green 4 blue 11 yellow marbles 25 total.
You randomly draw 2 marbles what is the probability of neither being yellow? I said .56% or 14/25 (or should it be 14/25 X 13/24 = )

#### soroban

##### Elite Member
Hello, deevicsm!

Jar containing 3 red, 7 green, 4 blue, 11 yellow marbles ... 25 total.
You randomly draw 2 marbles.
What is the probability of neither being yellow?
Your first answer is the probability of getting a non-yellow in one draw.

The prob. of a non-yellow on the 1<sup>st</sup> draw: $$\displaystyle \,\frac{14}{25}$$
The prob. of a non-yellow on the 2<sup>nd</sup> draw: $$\displaystyle \,\frac{13}{24}$$
Therefore: $$\displaystyle \,P(\text{two non-yellows})\;=\;\frac{14}{25}\,\time\frac{13}{24}\;=\;\frac{91}{300}\;\approx\;30\%$$