permutations and combinations # 6-7 and N.R. 2

6. As a designer, Sarah has 5 tints of colour to use in decorating her living room. If Sarah plans to use at least 4 tints, how many combinations can she select? A. 5 B. 6 C. 16 D. 26 Hint: Sarah may use 4 tints or 5 tints. Numerical Response 2. Determine the number of paths from A to B, if movement to the right and down along the lines shown is all that is permitted. B Hint: Consider the number of 'blocks' that can be travelled in each direction, and use permutations with repetitions. 7. In how many ways can a group of 15 students trying out for School Idol be divided into 3 groups, where there are 4 students in one group, 3 students in a second group, and 8 students in a third group. A. 96 B. 1 365 C. 225 225 D. 5 806 080 a student is in one group, he or she cannot be in another group. Hint: If