Question

Bob has a set of 10 colored markers in a backpack. One is yellow and one is blue. What is the probability Bob will reach into the backpack without looking and grab the yellow marker and then reach in a second time and grab the blue marker?

Answer 1

4/8 because if 2 already got pulled theres only 8 left four blue four yellow theres a 4 out od 8 chance youll pull them like that again

Answer 2

Answer:

The probability is 1%, really low.

Step-by-step explanation:

We know that there are 10 colored markers, and one of them is yellow, and another one of them is blue.

So, the probability of each one is

$P_{yellow}=\frac{1}{10}\\P_{blue}=\frac{1}{10}$

Now, let's assume that once you take a marker, you won't return it back in the backpack, this means the total number of elements is variable.

So, the probability of getting the yellow one and the blue one in to attempts is

$P=\frac{1}{10}\frac{1}{9}=\frac{1}{90} =0.01 (or \ 1\%)$

Observe that the second propability changes, that's because one you take out one marker, you won't place it back, so the total number of markers in the second attempt is nine.

Therefore, the probability is 1%, really low.