probability in word problems

Question

In Algebra 1 I am given the following problem:

 

A bowl contains 18 white, 10 black, and 4 red buttons of uniform size and shape. If one button is drawn at random... a. What is the probability that it is red? b. What is the probability that it is red or black? c. If the two buttons are drawn randomly from the bowl, what is the probability that the first is red and the second black if the buttons are drawn without replacement?

Please help me.

Answer 1

18/32 or 1/2 are white

10/32 or 5/16 are black

4/32 or 1/8 are red.

 

a. 1/8 are red, so the probability is 1/8

b. Add the red and black together.

      10/32 + 4/32 = 14/32 = 7/16

c. probability of red in first draw = 1/8

   In the second draw, there are now 31 buttons with 10/31 being black, so

   probability in second draw is 10/31

  You multiply these two events together, so 1/8 x 10/31 = 10/248 = 5/124

 

 

 

Have a great day!

Colossians 3:23