Question 477451

b) at least 3 members of the committee are physicists. 

possible ways are : 

1. 3 physicists and 3 from chemists and mathematicians

2. 4 physicists and 2 from chemists and mathematicians

3. 5 physicists and 1 from chemists and mathematicians


total number of ways = 5C3 * 7C3 + 5C4 * 7C2 + 5C5 * 7C1 


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