/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 35 The length in inches of a cricke... [FREE SOLUTION] | 91Ó°ÊÓ

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The length in inches of a cricket chosen at random from a field is a random variable \(X\) with mean 1.2 inches and standard deviation 0.25 inches. Find the mean and standard deviation of the length \(Y\) of a randomly chosen cricket from the field in centimeters. There are 2.54 centimeters in an inch.

Short Answer

Expert verified
The mean is 3.048 cm and the standard deviation is 0.635 cm.

Step by step solution

01

Understand the Conversion Factor

The problem states that there are 2.54 centimeters in an inch. This means to convert any length measurement from inches to centimeters, we multiply by 2.54.
02

Convert the Mean to Centimeters

The mean length of the cricket in inches is 1.2 inches. To find the mean length in centimeters, multiply by the conversion factor: \( \text{mean in cm} = 1.2 \text{ inches} \times 2.54 \text{ cm/inch} = 3.048 \text{ cm} \).
03

Convert the Standard Deviation to Centimeters

The standard deviation of the cricket's length in inches is 0.25 inches. Like we did for the mean, we multiply the standard deviation by the conversion factor to convert it to centimeters: \( \text{standard deviation in cm} = 0.25 \text{ inches} \times 2.54 \text{ cm/inch} = 0.635 \text{ cm} \).

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Mean
The mean is a fundamental concept in statistics, often referred to as the average. It represents the midpoint of a data set and provides a simple summary of a collection of numbers. To find the mean of a set of values, you sum all the values and divide by the number of values in the set. This measure gives you a sense of the typical size within a data set.
For instance, in the case of the cricket's length in inches, the mean is given as 1.2 inches. This means that if you were to randomly select a cricket from the field, its length would typically be around 1.2 inches. The mean provides a single value that summarizes the central tendency of all the crickets' lengths.
When converting this mean to another unit, like centimers, it is important to apply the same conversion factor that translates each unit consistently, ensuring accuracy across measurements.
Standard Deviation
Standard deviation is a measure of how spread out the numbers in a data set are around the mean. It quantifies the amount of variation or dispersion, indicating how much individual values typically differ from the average value.
For the cricket length, a standard deviation of 0.25 inches tells us that most crickets are within plus or minus 0.25 inches of the mean length of 1.2 inches. A small standard deviation indicates that the lengths are closely clustered around the mean, while a larger standard deviation would indicate more spread out lengths.
The process of converting the standard deviation into different units, like centimeters, is similar to converting the mean. You multiply the standard deviation by the conversion factor (here, 2.54 cm/inch) to maintain the understanding of variability in the new unit system.
Unit Conversion
Unit conversion is an essential tool for making calculations in different measuring units comparable. This process involves using a conversion factor, a numerical factor that translates one unit of measure into another, maintaining the correct equivalencies.
In the exercise, the unit conversion factor was 2.54, translating inches to centimeters. By multiplying the length in inches by 2.54, you convert the measurement to centimeters.
This method maintains consistency across calculations, ensuring that the mean and standard deviation accurately reflect measurements in whatever unit system chosen. It's crucial in fields like science and engineering, where precise measurement is necessary.
  • To convert a measurement, always use the precise conversion factor.
  • Check calculations to ensure both mean and deviation are accurately converted.

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Most popular questions from this chapter

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