Solve the Problem. -Scores on a Test Are Approximately Normally Distributed with a Distributed

question 184

Multiple Choice

Solve the problem.
-Scores on a test are approximately normally distributed with a mean of 70 and a standard deviation of 9. The teacher wants to give A's to the top 10% of students, B's to the next 25%, and C's to the
Next 42%. What is the bottom cutoff for a C grade? Round your answer to the nearest whole
Number.

• A)77
• B)68
• C)65
• D)63

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Definitions:

Side Chain

A group of atoms attached to a main part of a molecule and having a structure branching off from the main chain or ring in the molecule.

Amino Acid

Organic molecules that serve as the building blocks of proteins, containing both amino and carboxylic acid functional groups.

Aromatic Substructure

A part of a molecule containing an aromatic ring, characterized by a ring of atoms with resonance bonds creating stability.

Side Chain

The part of an amino acid that is distinct from the main backbone and determines the amino acid's properties.