Question

1. A comparison of life expectancy in random samples of 144 less developed countries and 144 industrialized countries reveals the following data.

	Less developed countries	Industrialized countries
Sample size	144	144
Mean	67.1	72.7
Standard deviation	28.9	4.2

1. Compute the 95% confidence interval for the average life expectancy in the less developed countries.
2. Compute the 95% confidence intervals for the average life expectancy in the industrialized countries.
3. Interpret the confidence interval in part (b).
4. Is there a significant difference in the average life expectancy between the less developed and industrialized countries? Explain

Answer 1