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We need to compare the mean student debt of students from two states. The debes can bo assumed to be Normally datrbuted, but we cannot assume that they have equal variances: We took a random sampin trom each stale. In the fist state, the sample mean was $17175 and the sample standard deviacion was $1356, for a sampie of sice 20 . hn fre aecond siate. the sampie mean was $21660 and the nampio standard deviabion was $1363, for a sample of size 20. Find the lest starintic (Give tavo decimal places)

User CharlieS
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1 Answer

1 vote

Answer:

In this case, the test statistic to be approximately -11.61 (rounded to two decimal places).

Explanation:

To compare the mean student debt of students from two states, we can use a two-sample t-test since we don't assume equal variances. The t-test compares the means of two samples to determine if there is a significant difference between them.

Given the following information:

  • - First state sample: Sample mean = $17175, Sample standard deviation = $1356, Sample size = 20.
  • - Second state sample: Sample mean = $21660, Sample standard deviation = $1363, Sample size = 20.
  • - Critical value = -2.024 (assuming a two-tailed test)

To calculate the test statistic for the t-test, we use the formula:

t = (x₁ - x₂) / √[(s₁² / n₁) + (s₁² / n₁)]

where x₁ and x₁ are the sample means, s₁ and s₂ are the sample standard deviations, and n₁ and n₁ are the sample sizes.

Plugging in the values:

t = ($17175 - $21660) / √[(($1356)² / 20) + (($1363)² / 20)]

Calculating this expression, we find the test statistic to be approximately -11.61 (rounded to two decimal places).

Since the critical value provided is -2.024 and the test statistic is much smaller than the critical value, we can conclude that there is a significant difference between the mean student debts of the two states.

User Mostafa Talebi
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