Question

2. A cereal company is interested in determining if there is a difference in the variation of the weights for 24-ounce and 48-ounce boxes of cereal.  A random sample of 18 (eighteen) 24-ounce boxes of cereal produced a sample variance (S₁²) of 0.005 oz².  A sample of thirty-one (31) 48-ounce boxes of cereal produced a sample variance (S₂²) of 0.004 oz².  Use the sample information to construct a 90% confidence interval estimate for the true population ratio of. The point estimate for the ratio is calculated as  which equals 1.25 (You need to find the lower and upper limits of the confidence interval by completing parts (a) and (b) below).

1. Find the F interval coefficients, the upper F value and the lower F value from the F-table (or from software) for computing a 90% confidence interval estimate of the ratio of the two population variances. Note: the point estimate of the ratio is given as S₁²/ S₂²

F_upper=

F_Lower=

2. Construct the 90% confidence interval for the ratio of the two population variances.

3. Based on the confidence interval calculated in part (b) what would you conclude about the two population variances?

1. The confidence interval includes 1. Conclude that the two population variances are equal
2. The confidence interval includes 1. Conclude that the two population variances are not equal
3. The confidence interval does not include 1. Conclude that the two population variances are equal
4. The confidence interval does not include 1. Conclude that the two population variances are not equal

Answer 1