Many elementary school students in a school district currently have ear infections. A random sample of children in two different schools found that 17 of 50 at one school and 15 of 30 at the other have ear infections. At the 0.05 level of significance, is there sufficient evidence to support the claim that a difference exists between the proportions of students who have ear infections at the two schools?
A) Yes, because the test value -12.50 is outside the noncritical region -1.96

Question

Many elementary school students in a school district currently have ear infections. A random sample of children in two different schools found that 17 of 50 at one school and 15 of 30 at the other have ear infections. At the 0.05 level of significance, is there sufficient evidence to support the claim that a difference exists between the proportions of students who have ear infections at the two schools?
A) Yes, because the test value -12.50 is outside the noncritical region -1.96 < z < 1.96.
B) No, because the test value -1.41 is inside the noncritical region -1.96 < z < 1.96.
C) No, because the test value -1.85 is inside the noncritical region -1.96 < z < 1.96.
D) Yes, because the test value -6.96 is outside the noncritical region -1.96 < z < 1.96.

Quizplus · Accepted Answer

The Answer of Many elementary school students in a school district currently have ear infections. A random sample of children in two different schools found that 17 of 50 at one school and 15 of 30 at the other have ear infections. At the 0.05 level of significance, is there sufficient evidence to support the claim that a difference exists between the proportions of students who have ear infections at the two schools?
A) Yes, because the test value -12.50 is outside the noncritical region -1.96 < z < 1.96.
B) No, because the test value -1.41 is inside the noncritical region -1.96 < z < 1.96.
C) No, because the test value -1.85 is inside the noncritical region -1.96 < z < 1.96.
D) Yes, because the test value -6.96 is outside the noncritical region -1.96 < z < 1.96.

Many Elementary School Students in a School District Currently Have