These two problems almost always show up on standardized math test in 9th grade and up. Can you work them? Back with answers tomorrow.

1. A bag contains 3 green marbles, 5 blue marbles, and 2 yellow marbles. One marble is drawn from the bag. Find the probability that the marble is blue.

*ANSWERS***!!!!!!!!!!!!!!!! Thanks for the emails. Most of you were right on! If you didn’t write in, check your answers now.**

*1. 10 Total Marbles. Probability of selecting a green marble is 2 out of 10, or 2/10, or 1/5. Pr(Blue) is 5/10 or 1/2. Pr(Yellow) =2/10=1/5. *

2. Mr. A’s 1st Period class has 5 girls and 7 boys. Ms. Z’s 1st Period class has 8 girls and 7 boys. One student is to be selected at random from each class to go to the guidance office to pick up copies of next semester’s course offerings. Find the *probability* that Mr. A *and* Ms. Z each pick a boy.

**ANSWER:**

Probability of Mr. A choosing a boy is 7 out of 12 or 7/12. Pr (Mrs.Z selecting a boy)=7/15. Pr (Both selecting boys)= 7/12 times 7/15 or 49/180. Or 1/3.67. Or 0.27222. Or a little less than 1/3.

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