In how many ways, can the letters of the word 'ASSASSINATION' be arranged, so that all the S are together?

When All S are taken together, then ASSASSINATION has 10 letters .
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So, 10 letters in total can be arranged in 10 ! ways .
[∵ All 'S' are considered as 1]
But, here are 3 'A' and 2'I' and 2 'N' .
∴ Required number of ways = 10 ! / (3 ! x 2 ! x 2 !) = 151200