Question

How many 4 letters words can be formed for word logarithms?

Answer 1

Since none of the letters in the 10-letter long “logarithms” is a repeat: P(10,4)=5040. In other words, there 10 letters to choose for the first of the new 4-letter word, then 9 for the second, 8 for the third, and 7 for the fourth.