Chapter 7 Class 11 Permutations and Combinations
Chapter 7 Class 11 Permutations and Combinations
Last updated at Dec. 24, 2019 by Teachoo
Ex7.1, 6 Given 5 flags of different colours, how many different signals can be generated if each signal requires the use of 2 flags, one below the other? A signal can have only 2 flags The required number of signals = 5 × 4 = 20