The number of ways of arranging the letters of the word DEVIL so that ...
Total arrangement with the letters of the word DEVIL = 5! = 120
Number of arrangement starting with D = 24 = 4!
Number of arrangement end with L = 24 = 4!
Number of arrangement that begin with D and end with L is 6
Number of arrangements required = 120 – (24 + 24 – 6) = 78
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The number of ways of arranging the letters of the word DEVIL so that ...
To solve this problem, we can use the concept of permutations.
Arrangement of the word "DEVIL"
The word "DEVIL" contains 5 letters. Let's consider the arrangements of these letters when neither D is the first letter nor L is the last letter.
Case 1: D is the first letter
If D is the first letter, then we have 4 remaining letters (E, V, I, L) to arrange. The number of ways to arrange these 4 letters is 4!.
Case 2: L is the last letter
If L is the last letter, then we have 4 remaining letters (D, E, V, I) to arrange. The number of ways to arrange these 4 letters is also 4!.
However, in these arrangements, there is an overlap. When we consider the case where D is the first letter, it includes the arrangement where D is the first letter and L is the last letter. Similarly, when we consider the case where L is the last letter, it includes the arrangement where D is the first letter and L is the last letter.
Overlap
To find the overlap, we need to count the number of ways to arrange the remaining 3 letters (E, V, I) when D is the first letter and L is the last letter. The number of ways to arrange these 3 letters is 3!.
Calculating the answer
To find the total number of arrangements where neither D is the first letter nor L is the last letter, we subtract the overlap from the total number of arrangements.
Total arrangements = (Case 1) + (Case 2) - Overlap
Total arrangements = 4! + 4! - 3!
Total arrangements = 24 + 24 - 6
Total arrangements = 42
Therefore, the correct answer is option c) 42.