Independent & Dependent problem

Question

 a bag contains 5 red apples and 3 yellow aplles. What is the probability of picking 2 red apples without the first being replaced.

Answer 1

1.  So, we start of with the total apples in the bag.  5 red + 3 yellow = 8 apples total.

2.  Next, we start with the probability of picking the first red apple.  We know that 5/8 of the apples in the bag are red, so that is our first probability.  

3.  If we remove that apple, the number of apples in the bag changes from (5 red - 1 red = 4 red)/(8 total- 1 apple = 7 total).  Our new probability is 4/7.  

 

4.  In order to find the probability of picking two red apples without the first being replaced, we multiply the 2 probabilities. (5/8) * (4/7) = 20/56.  Round that down to find 5/14, is our answer.