Quantitative Aptitude
PERMUTATION AND COMBINATION MCQs
Permutations And Combinations
Total Questions : 444
| Page 7 of 45 pages
Answer: Option B. -> 5
Answer: Option D. -> 2
Answer: Option A. -> 242
Question 64. There are 20 couples in a party. Every person greets every person except his or her spouse. People of the same sex shake hands and those of opposite sex greet each other with a Namaste (It means bringing one's own palms together and raising them to the chest level). What is the total number of handshakes and Namaste's in the party?
Answer: Option B. -> 1140
Question 65. In a certain laboratory, chemicals are identified by a colour-coding system. There are 20 different chemicals. Each one is coded with either a single colour or a unique two-colour pair. If the order of colours in the pairs does not matter, what is the minimum number of different colours needed to code all 20 chemicals with either a single colour or a unique pair of colours?
Answer: Option B. -> 6
Answer: Option C. -> 21
Answer: Option D. -> 18 × 10!
Answer: Option B. -> 72
Answer: Option B. -> 29
Answer: Option B. -> 1512