The problem asks us to determine if there are any outliers in the given data set: $51, 56, 70, 74, 76, 76, 77, 80, 81, 83$ using the Interquartile Range (IQR) method.

Probability and StatisticsDescriptive StatisticsOutlier DetectionInterquartile Range (IQR)Data Analysis
2025/3/27

1. Problem Description

The problem asks us to determine if there are any outliers in the given data set: 51,56,70,74,76,76,77,80,81,8351, 56, 70, 74, 76, 76, 77, 80, 81, 83 using the Interquartile Range (IQR) method.

2. Solution Steps

First, we need to find the first quartile (Q1), the third quartile (Q3), and then calculate the IQR.
The given data set is already sorted in ascending order: 51,56,70,74,76,76,77,80,81,8351, 56, 70, 74, 76, 76, 77, 80, 81, 83.
There are n=10n = 10 data points.
Q1 is the median of the lower half of the data.
The lower half of the data is 51,56,70,74,7651, 56, 70, 74, 76.
Q1 is the median of this lower half, which is 7070.
Q3 is the median of the upper half of the data.
The upper half of the data is 77,80,81,8377, 80, 81, 83.
Q3 is the median of this upper half, which is 77+802=1572=78.5\frac{77 + 80}{2} = \frac{157}{2} = 78.5.
The IQR is the difference between Q3 and Q1:
IQR=Q3Q1=78.570=8.5IQR = Q3 - Q1 = 78.5 - 70 = 8.5
Now, we need to calculate the lower and upper bounds for outliers.
Lower bound =Q11.5×IQR=701.5×8.5=7012.75=57.25= Q1 - 1.5 \times IQR = 70 - 1.5 \times 8.5 = 70 - 12.75 = 57.25
Upper bound =Q3+1.5×IQR=78.5+1.5×8.5=78.5+12.75=91.25= Q3 + 1.5 \times IQR = 78.5 + 1.5 \times 8.5 = 78.5 + 12.75 = 91.25
Any data points below the lower bound or above the upper bound are considered outliers.
The data points are 51,56,70,74,76,76,77,80,81,8351, 56, 70, 74, 76, 76, 77, 80, 81, 83.
The minimum value is 5151 and the maximum value is 8383.
Since 51<57.2551 < 57.25, 5151 is not an outlier because it must be less than 57.25 to be an outlier.
Since 83<91.2583 < 91.25, 8383 is not an outlier.
Therefore, there are no outliers.

3. Final Answer

D. There are no outliers.

Related problems in "Probability and Statistics"

The problem provides a frequency distribution table of marks obtained by students. Part (a) requires...

ProbabilityConditional ProbabilityWithout ReplacementCombinations
2025/6/5

The problem is divided into two questions, question 10 and question 11. Question 10 is about the fre...

Frequency DistributionCumulative FrequencyOgivePercentileProbabilityConditional ProbabilityCombinations
2025/6/5

A number is selected at random from the integers 30 to 48 inclusive. We want to find the probability...

ProbabilityPrime NumbersDivisibility
2025/6/3

The problem describes a survey where 30 people answered about their favorite book genres. The result...

PercentagesData InterpretationPie ChartFractions
2025/6/1

The problem asks us to determine if there is a statistically significant difference in promotion rat...

Hypothesis TestingChi-Square TestContingency TableStatistical SignificanceIndependence
2025/6/1

We are given a contingency table showing the number of students from different majors (Psychology, B...

Chi-Square TestContingency TableStatistical InferenceHypothesis Testing
2025/6/1

The problem describes a scenario where a pizza company wants to determine if the number of different...

Chi-Square TestGoodness-of-Fit TestHypothesis TestingFrequency DistributionP-value
2025/6/1

The problem asks to test the significance of three chi-square tests given the sample size $N$, numbe...

Chi-square testStatistical SignificanceDegrees of FreedomEffect SizeCramer's VHypothesis Testing
2025/5/29

The problem asks us to compute the expected frequencies for the given contingency table. The conting...

Contingency TableExpected FrequenciesChi-squared Test
2025/5/29

The problem asks us to estimate the chi-square value when $n=23$ and $p=99$, given a table of chi-sq...

Chi-square distributionStatistical estimationInterpolation
2025/5/27