Answer:
80
Step-by-step explanation:
A certain company employs 6 senior officers and 4 junior officers. If a committee is to be created that is made up of 3 sr officers and 1 jr officer, how many different committees are possible?
8
24
58
80*
210
I initially got this one wrong, but after I saw the answer which is 80, I was able to solve it. But im not sure if this is the proper way of solving it, or if someone can suggest a more efficient way of solving it?
This is what I did, which was wrong:
Sr Officers + Jr Officers
(6!/3! 3! = 20) + (4!/3! = 4) = 24
It seems like the correct answer is:
Sr Officers X Jr Officers
(6!/3! 3! = 20) x (4!/3! = 4) = 80
If this is the most efficient way of solving, when do you know when to add them as opposed to multiplying them in this case?
The answer is <span>2^7 = 128<span>
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Multiplying with 6 is like multiplying with 3 because, you just double it. Let's say 3 × 4 = 12
Its the same as 6 × 2 = 12 ... which is just 3 + 3 + 3 + 3 . ((:
