Hi
1. Go to this page to read the theory about tree diagrams and solve the questions at the end.
2. Now some problems. Solve them in a word document. If needed, draw tree diagrams or contingency tables. Send me the file, of course.
- A box has 8 red balls, 5 yellow and 7 green. If a ball is extracted at random, calculate the probability that it will be:
- Red.
- Green.
- Yellow.
- Not red.
- Not yellow.
-A box contains three red balls and seven blue. Two balls are drawn at random. Define the sample space and find the probability of events when:
- The first ball is replaced before the second is drawn.
- 2The first ball is not replaced before the second is drawn.
-A ball is drawn from a box containing 4 red balls, 5 blue and 6 green. What is the probability that the ball will be red or white? What is the probability that it is blue? If you take out another ball, what are the chances of being red?
-In a class there are 10 blonde girls, 20 brunette girls, 5 blonde boys and 10 brown-haired boys. If all 45 students attend class on a particular day, find the probability that a student selected at random will be:
- A boy.
- A brunette girl.
- A boy or girl.
- If the student is a boy, find the probability that he’s blonde.
- If the student is brown-haired, find the probability that she’s a girl.
-A die is rigged so that the probabilities of obtaining the different faces are proportional to the numbers on the faces (For example: A five is five times more likely to be rolled than a one). Find:
- The probability of obtaining a 6.
- The probability of obtaining an odd number.
