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Question
A Question In My Summer Homework Said
"Tamara wraps 12 gift boxes in red paper and 8 gift boxes in blue paper. She puts a CD in 8 of the red boxes and 2 of the blue boxes. What is the probability of picking a box with a CD if a person randomly chooses a gift box?"
The Third part of The Question Says,
"Write the formula for probability in words. Then substitute numbers for the probability and simplify."
I Don't Understand What It Means By 'The Formula For Probability'.
If You Can Help Me I Would Be Very Grateful, If You Can't I Thank For At Least Trying To.

"Tamara wraps 12 gift boxes in red paper and 8 gift boxes in blue paper."
12 + 8 = 20 boxes in all

"She puts a CD in 8 of the red boxes and 2 of the blue boxes."
10 of the boxes contain a CD

"What is the probability of picking a box with a CD if a person randomly chooses a gift box?"
probability of picking a CD box = (number of CD boxes)/(total number of boxes)
probability = 10/20 = 50%

Please verify the logic! I have had very little instruction in stats.

Volunteer

#### Janet Yang

##### Expertise

I can answer questions in Algebra, Basic Math, Calculus, Differential Equations, Geometry, Number Theory, and Word Problems. I would not feel comfortable answering questions in Probability and Statistics or Topology because I have not studied these in depth.

##### Experience

I tutor students (fifth through twelfth grades) and am a Top Contributor on Yahoo!Answers with over 24,000 math solutions.

Publications
Co-author of An Outline of Scientific Writing: For Researchers With English as a Foreign Language

Education/Credentials
I have a Bachelor's degree in Applied Mathematics from the University of California at Berkeley.

Past/Present Clients
George White Elementary School. Homework Help program at the Ridgewood Public Library, Ridgewood, NJ. Individual students.