The number of words that can be arranged with the letters of the word CALCULATE such that each word starts and ends with a consonant is

The number of arrangements like C....C =7! / (2!*2!) :same will be the no. of arrangements like L......L

Again,no of arrangements beginning or ending with C,L = (7! / 2!) * 2.

Also no of words with (C or L)at one end and T at other end is =2*2!*(7! / (2!*2!))
Hence the required number is = 7! / (2!*2!)+(7! / 2!) * 2+2*2! * (7! / (2!*2!))= 12600