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Solution — 2021 Question 7 Permutations & Combinations

We take out the letters P and G and rearrange the rest first (7! ways)

inserting letters to have 5 in between

We now try to insert P and G such that there are 5 letters in between them. There are 3 possible ways

Finally, there are 2! ways to arrange P and G

Number of arrangements=7!×3×2!=30240∎
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