Question 1202245: 1a. Find the permutation from word ABRACADABRA
A. Total number of permutation of word ABRACADABRA
B. Begins with A
C. Begins with E and ends with R
D. Begins with A and ends with A
E. Does not begins with A
Answer by ikleyn(52754)   (Show Source):
You can put this solution on YOUR website! .
In this my post, I will solve (C) and will make a note about the rest.
In (C), the answer is 0 (zero), since the letter "E" does not participate in the word "ABRACADABRA",
as it is easily to see.
Regarding the use of the term " permutations ", in problems with repeating letters
usually use the term "arrangements" or "distinguishable arrangements/permutations"
to avoid ambiguity and to make the language adequately correct, clean and accurate.
As I see, the personal on the opposite side of the Internet intensively works every day
to create their own problems on their own, without having knowledge on an appropriate/standard Math terminology.
May be, it makes sense to consider hiring specialists to improve a quality of your production,
which, without this preventive measure, remains at the alarmingly low level . . .
You need a person (or even a team of specialists) that will edit EVERY your composition EVERY DAY,
on the 24/7, or even 25/8 basis.
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