SOLUTION: Seven-letter words can be formed without repetition from the letters of the word INCLUDE; 5040. How many have the letters N and D separated by exactly two letters?

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Question 1149533: Seven-letter words can be formed without repetition from the letters of the word INCLUDE; 5040. How many have the letters N and D separated by exactly two letters?
Found 2 solutions by greenestamps, Alan3354:
Answer by greenestamps(13198) About Me  (Show Source):
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(1) The N and D can be separated by exactly 2 other letters if they in positions 1 and 4, or 2 and 5, or 3 and 6, or 4 and 7. That's 4 choices.

(2) For any of the choices from (1), either the N or D can be first. That's 2 choices.

(3) For any of the choices from (1) and (2), the remaining 5 letters can be arranged in 5!=120 ways.

ANSWER: (4)*(2)*(120) = 960

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Seven-letter words can be formed without repetition from the letters of the word INCLUDE; 5040. How many have the letters N and D separated by exactly two letters?
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Few 7-letter words, if any, can be made from those.
Other words, but not with 7 letters are:
DUE
ID
DUNE
NUDE
DUEL
DINE
........
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If you mean just combinations of letters you should say that.