Hi 365 team and aspiring data scientists,
I have a quick Q about the quiz no 3 in the “Computing Variations with Repetition” module.
Why is 8 to the power of 4 (8^4) not the correct answer? Can someone help me explain this?
I would very much appreciate it.
Hey 365 team, can someone help with this query? I have been waiting for weeks now 🙁
Try thinking about the quiz the following way:
- How many different 4-letter codes are there so that each letter is one of the letters in the word “password”?
The “trick” here is that the word “password” has only 7 distinct letters: P, A, S, W, O, R, D. Therefore we need to arrange 4 out of 7 letters, allowing for repetition and their order is relevant (each 4-letter code is a unique code; the lock would not open if the code was PASW and you typed WASP). So you end up with:
V(n=7,p=4) = 7^4
Hope this helps!
Thanks a lot for this, Jacob! This finally clears my doubt 🙂 truly appreciate your effort.