Following are the calculation to the 2-letter combinations:
Given:
Please fine the question.
To find:
2-letter combinations
Solution:
Using formula:
[tex]^{n}{C_{r}} =\frac{n!}{r!(n-r)!}[/tex]
putting the value into the above formula:
[tex]n=4\\\\r=2[/tex]
[tex]\bold{^{4}{C_{2}} =\frac{4!}{2!(4-2)!}}[/tex]
[tex]\bold{=\frac{4!}{2!(2)!}}\\\\\bold{=\frac{4\times 3 \times 2 \times 1}{2 \times 1 \times 2 \times 1 }}\\\\\bold{=\frac{4\times 3 \times 2 \times 1}{4}}\\\\\bold{=\frac{ 3 \times 2 \times 1}{1}}\\\\\bold{=6}\\\\[/tex]
Therefore, the final answer is "Option b".
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brainly.com/question/17512033
