Question

Scientists want to estimate the difference in twinning rate of two lines of beef cattle that have been selected for increased frequency of twin births. In last spring's calving season, 40 of the 100 cows in Line 1 and 30 of the 100 cows in Line 2 gave birth to twins.

Construct a 90% confidence interval for the true difference in population proportions of cows giving birth to twins in Lines 1 and 2. In the interest of time you can assume that the sample sizes are large enough that it is appropriate to use a large-sample confidence interval.

A) (-0.01035, 0.21035)

B) (-0.0925975, 0.1074025)

C) (-1.034995, 21.034995)

D) (0.05, 0.15)

Answer 1

=  (-0.01035, 0.21035)

Answer : option ( A )