Combinatorics question about the four-letter sequence "GRIT"

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SUMMARY

The discussion centers on calculating the number of nine-letter arrangements of the word "FULBRIGHT" that contain the four-letter sequence "GRIT." The correct approach involves treating "GRIT" as a single unit, reducing the problem to arranging six units (GRIT and the remaining letters). The calculation confirms that there are 720 valid arrangements, derived from the formula 6 x 5! = 720. This method effectively simplifies the combinatorial problem by consolidating the four-letter sequence.

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Homework Statement
Given the letters in "FULBRIGHT" how many contain the four-letter sequence "GRIT".
Relevant Equations
6 x 5!
Question: "A total of 9! = 362880 different nine-letter ‘‘words’’ can be produced by rearranging the letters in FULBRIGHT. Of these, how many contain the four-letter sequence GRIT?"

Solution: There are six ways of getting the word "GRIT" with five letters left over giving 6 x 5! = 720 possibilities.

There is no answer in my book so just wanted to verify whether my solution is correct or not.
 
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Yes, you can consider GRIT as a single letter X. So ##6!##
 
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Thank you I didn't think of it that way but that does make sense!
 

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