The Average Diameter of Sand Dollars on a Certain Island

question 37

Multiple Choice

The average diameter of sand dollars on a certain island is 3.50 centimeters with a standard deviation of 1.00 centimeters. If 25 sand dollars are chosen at random for a collection, find the probability that the average diameter of those sand dollars is more than 3.28 centimeters. Assume that the variable is normally distributed.

• A) 0.636
• B) 0.800
• C) 0.364
• D) 0.864

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Definitions:

Mid-Ocean Ridge

An underwater mountain range formed by plate tectonics, where new oceanic crust is created.

Transform Fault

A strike-slip fault that accommodates the horizontal movement of one tectonic plate past another.

Mid-Atlantic Ridge

An underwater ridge located in the Atlantic Ocean, forming a divergent tectonic plate boundary that separates the Eurasian and North American plates in the north and the African and South American plates in the south.

Seafloor Spreading

A geologic process in which tectonic plates move apart from each other, allowing magma to rise and solidify as new oceanic crust.