1. Halmi generated four odd numbers at random using technology, and obtained 3,7,11, and 13. Can he conclude that all odd numbers are prime numbers? Explain your answer.
2. there are 22 children in a kindergarten class. Each reports having at least one cat or dog. Thirteen students have a cat and 14 have dog. What is the probability that given student has both a cat and a dog?
3. A team of students consisting of one from each grade, 9 to 12, is being chosen. Two students are eligible from Grade9, three from Grade 10, two from Grade 11, and two from Grade 12. Use an appropriate diagram to illustrate the number of choices available to the team organizers.
4. A club has 20 members. in how many ways could an excutive committee consisting of a president, vice president, secretary, membership director, and treasurer be named? Show two methods.
5. Five students are to be selected from 6 grade 9 students, 10 grade 10 students, 8 grade 11 students, and 9 grade 12 students. In how many ways could they all be from the same grade.