AA1: DISCRETE MATHS-REVISION QUESTIONS AND CORRECT ANSWERS (ALL THE HELP YOU NEED TO PREPARE FOR EXAMS)

Document Content and Description Below

Discrete Mathematics: Revision Questions (and answers). Rev 12.14.17 Q1. Find the number of different arrangements of the letters in the word: MISAPPREHENSION. Answer: 15! 2!2!2!2!2! Of these arr... angements, (a) how many have all the vowels together? Answer: 10! 2!2!2! 6! 2!2! (b) how many start and end with N? Answer: 13! 2!2!2!2! (c) how many start or end with N? Answer: Use the PIE: 14! 2!2!2!2! start with N, 14! 2!2!2!2! end with N, and 13! 2!2!2!2! start and end with N. So the answer is 2 × 14! 2!2!2!2! − 13! 2!2!2!2! (d) how many have all the letters in alphebetical order? Answer: Just 1 Q2. (a) The sets A and B are such that |A| = 10 and |B| = 20. What is the largest possible value of |A ∪ B|? Answer: 30 What is the largest possible value of |A ∩ B|? Answer: 10 What is the value of |A ∪ B| + |A ∩ B| Answer: 30? (b) Suppose that four sets are such that • each set has 30 elements; • each pair of sets share 10 elements, and • each triple of sets share 5 elements. If the union of all four sets has 80 elements, how many elements are there in the intersection of all four sets? [Show More]

Last updated: 1 year ago

Preview 1 out of 2 pages