SOLUTION: Dear tutor, please help me..how many probability for word COMBINE to : - start with C and end with E? - start with C or end with E? - with I and N separated?

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Question 619337: Dear tutor, please help me..how many probability for word COMBINE to :
- start with C and end with E?
- start with C or end with E?
- with I and N separated?
- with alternating vowels and consonants?
-if a 5 letter word instead of 7 letter word is made from COMBINE, how many probability are that has exactly 3 consonants?
greatly appreciate. thank you
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
how many probability for word COMBINE to :
- start with C and end with E?
1st letter: 1 way
Last letter: 1 way
5 letters in-between: 5! ways
P(stated condition) = 5!/7! = 1/(7*6) = 1/42
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- start with C or end with E?
P(start C OR end E) = P(start C) + P(end E) - P(start C AND end E)
= (6!/7!) + 6!/7! - 1/42
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= 2/7 - 1/42
= 12/42 -1/42 = 11/42
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COMBINE
- with I and N separated?
I and E separated: 5 ways
permute E and N: 2 ways
arrange other 5 letters: 5! ways
P(stated condition) = (5*2*5!)/7! = 10/42 = 5/21
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I'll leave the rest to you.
Cheers,
Stan H.
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- with alternating vowels and consonants?
-if a 5 letter word instead of 7 letter word is made from COMBINE, how many probability are that has exactly 3 consonants?

SOLUTION: Dear tutor, please help me..how many probability for word COMBINE to : - start with C and end with E? - start with C or end with E? - with I and N separated? - with alternating