SOLUTION: Find the number of way of arranging all the letters of the word TENNESSEE: a) the FIRST two letters must be EE b) the FIRST can NOT be EE

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Question 462899: Find the number of way of arranging all the letters of the word TENNESSEE:
a) the FIRST two letters must be EE
b) the FIRST can NOT be EE

Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
Find the number of way of arranging all the letters of the word TENNESSEE:
a) the FIRST two letters must be EE
Examples:  EESENTNSE,  EEETSENSN, EENNSSTEE

So we just have to fill in the 7 letters after EE
from the 7 letters TENNESS in the blanks of:

E E _ _ _ _ _ _ _

Among the 7 letters of TENNESS there are 2 
indistinguishable E's, 2 indistinguishable
N's, and 2 indistinguishable S's, so

the answer is 7%21%2F%282%212%212%21%29+=+630             

b) the FIRST can NOT be EE
First we find all the distinguishable arrangements of 
the 9 letters TENNESSEE and then subtract the results of
part (a)

Among the 9 letters of TENNESSEE there are 4 
indistinguishable E's, 2 indistinguishable N's, and
2 indistinguishable S's, so the number of 
distinguishable arrangements of TENNESSEE is

9%21%2F%284%212%212%21%29+=+3780

But we must subtract all the distinguishable 
arrangements which begin with EE, so the answer
is 3780 - 630 = 3150

Edwin