Use the Combinations Formula
Use the Formula For $$\mathrm { n } ^ { \mathrm { C } _ { \mathrm { r } } }$$

question 174

Multiple Choice

Use the Combinations Formula
Use the formula for
$$\mathrm { n } ^ { \mathrm { C } _ { \mathrm { r } } }$$ to evaluate the expression.
-In a student government election, 5 seniors, 3 juniors, and 2 sophomores are running for election. Students elect four at-large senators. In how many ways can this be done?

• A)210
• B)5040
• C)151,200
• D)30

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Definitions:

Donor Blood

Blood collected from a healthy individual used for transfusion to a recipient in need.

Antigen B

A specific marker, usually a protein, on the surface of certain blood cells, critical in determining blood type.

Anti-B Antibodies

Antibodies present in the plasma of individuals with type A blood, reacting against B antigens found on red blood cells in type B or AB blood.

Incompatible Donor(s)

Refers to a donor whose organs, tissues, or blood type do not match the recipient's, leading to possible rejection if transplanted.