Math Problem Statement

A study conducted stating does the temperature conditions affect the growth of height

in children. The data was collected from two different locations A and location B. Check

whether the external condition of temperature is affecting the growth or not at a level of

significance of 5%.

A 98 102 96 104 100

B 100 105 98 102 104

Solution

To determine whether the external condition of temperature is affecting the growth of children's height at a 5% level of significance, we can use a hypothesis test. Since we are comparing the heights from two different locations (A and B), we can perform a two-sample t-test for the means.

Steps to Perform a Two-Sample t-Test:

  1. State the Hypotheses:

    • Null Hypothesis (H₀): There is no significant difference between the mean heights of children from locations A and B (i.e., temperature does not affect growth). H0:μA=μBH₀: \mu_A = \mu_B
    • Alternative Hypothesis (H₁): There is a significant difference between the mean heights of children from locations A and B (i.e., temperature affects growth). H1:μAμBH₁: \mu_A \neq \mu_B
  2. Calculate the Means and Standard Deviations:

    • Heights from location A: 98, 102, 96, 104, 100
    • Heights from location B: 100, 105, 98, 102, 104

    We will compute the means (xˉA\bar{x}_A and xˉB\bar{x}_B) and the standard deviations (sAs_A and sBs_B) for both samples.

  3. Determine the Degrees of Freedom and Compute the t-Statistic using the formula: t=xˉAxˉBsA2nA+sB2nBt = \frac{\bar{x}_A - \bar{x}_B}{\sqrt{\frac{s_A^2}{n_A} + \frac{s_B^2}{n_B}}} where:

    • nAn_A and nBn_B are the sample sizes for location A and B, respectively.
    • sA2s_A^2 and sB2s_B^2 are the variances (square of the standard deviations).
  4. Find the Critical Value for a two-tailed test at the 5% level of significance.

  5. Make a Decision:

    • If the computed t-value is greater than the critical value, reject the null hypothesis.
    • Otherwise, fail to reject the null hypothesis.

I'll now compute these values to perform the test.### Results of the Two-Sample t-Test:

  1. Means:

    • Location A: Mean height = 100.0
    • Location B: Mean height = 101.8
  2. Standard Deviations:

    • Location A: Standard deviation = 3.16
    • Location B: Standard deviation = 2.86
  3. t-Statistic: t=0.943t = -0.943

  4. p-Value: p=0.373p = 0.373

  5. Critical t-Value: For a 5% significance level and degrees of freedom ≈ 7.92, the critical t-value is approximately tcritical=2.31t_{\text{critical}} = 2.31.

Conclusion:

  • Since the absolute value of the computed t-statistic (t=0.943|t| = 0.943) is less than the critical value (2.31), and the p-value (0.373) is greater than 0.05, we fail to reject the null hypothesis.
  • Therefore, there is no statistically significant evidence to suggest that the external temperature conditions are affecting the growth of children's height at the 5% significance level.

Would you like further details on any of these steps or concepts?

Here are 5 related questions to explore further:

  1. What assumptions are made in a two-sample t-test, and are they satisfied here?
  2. How would the results change if the sample sizes were larger?
  3. What is the difference between a paired and an unpaired t-test?
  4. How would a one-tailed test differ from this two-tailed test?
  5. Can other factors besides temperature affect the height difference in children?

Tip: Always check the sample size and variance before choosing a t-test, as it influences the assumptions about equal or unequal variances.

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Math Problem Analysis

Mathematical Concepts

Statistics
Hypothesis Testing
Two-Sample t-Test

Formulas

t = (x̄A - x̄B) / sqrt((sA² / nA) + (sB² / nB))
Variance = s²
p-Value Calculation

Theorems

Central Limit Theorem
t-Distribution

Suitable Grade Level

Grades 10-12