Q: Find the number of different ways in which the 9 letters of the word GREENGAGE can be arranged if exactly two of the Gs are next to each other.

Its answer is 5040, but I don't get the method.

 5040

Step-by-step explanation:

GREENGAGE -->    GGG  R  EEE  N  A

The formula for a Permutation with duplicates is:

Where

Since we have a requirement that 2 of the G's must be next to each other, the numerator reflects as:

The denominator will have 3! to represent the G's

                                      and 3! to represent the E's

Solution:

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