Question: How many 2-letter code words can be formed from the letters B, R, K, L, E if no letter is repeated?…

How many 2-letter code words can be formed from the letters B, R, K, L, E if no letter is repeated? If letters can be repeated? If adjacent letters must be different? … There are possible 2-letter code words if no letter is repeated. (Type a whole number.)

Solution

To determine the number of possible 2-letter code words that can be formed from the letters B, R, K, L, E, with the condition that no letter is repeated, we proceed as follows: First, consider the selection for the first letter. There are 5 possible letters (B, R, K, L, E). For the second letter, since no letter can be repeated, we have 4 remaining choices. The number of possible 2-letter code words is calculated by multiplying the number of choices for each position: \[ 5 \times 4 = 20 \] Therefore, there are 20 possible 2-letter code words if no letter is repeated.