In a Manufacturing Process a Random Sample of 9 Bolts

question 24

Multiple Choice

In a manufacturing process a random sample of 9 bolts manufactured has a mean length of 3cm with a variance of 0.09.Assuming bolt length is normally distributed,what is the 90% confidence interval for the true mean length of the bolt?

• A)2.8355 to 3.1645
• B)2.5065 to 3.4935
• C)2.4420 to 3.5580
• D)2.8140 to 3.8160
• E)2.9442 to 3.0558

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Definitions:

Pentaradially Symmetrical

A form of symmetry found in some organisms, particularly sea stars, where their body can be divided into five or more equal parts.

Radially Symmetrical

An organism is described as radially symmetrical when its body structure can be sliced into symmetrical halves through any number of planes along its center.

Water Vascular System

Unique hydraulic system of echinoderms; functions in locomotion and feeding.

Echinoderms

A phylum of marine animals including starfish, sea urchins, and sea cucumbers, characterized by radial symmetry and a water vascular system.