Question

Find the number of ways so that letters of the word HISTORY can be arranged as begin with S and end with T

Answer 1

There are 7 letters in the word HISTORY

When word begins with S and ends with T.

All the letters of the word HISTORY are to be arranged among themselves such that arrangement begins with S and ends with T.

Other 5 letters can be filled between S and T among themselves in ⁵P₅ i.e., 5! ways

= 120 ways

∴ 120 words can be formed if arrangement begins with S and ends with T.