In independent random samples, 48 of 120 city residents and 45 of 150 suburban residents commute by bus. Find ${\hat{p}}_1-{\hat{p}}_2$ and its standard error, to three decimals.

In independent random samples, 70 of 200 rural households and 45 of 180 city households recycle batteries. Find ${\hat{p}}_1-{\hat{p}}_2$ and its standard error, to three decimals.

A cafeteria survey uses independent samples: 64 of 160 students at School A and 50 of 200 at School B choose salad. Find ${\hat{p}}_1-{\hat{p}}_2$ and its standard error, to three decimals.

Independent samples find 90 of 250 factory-line A parts and 84 of 200 line B parts have a cosmetic flaw. Find ${\hat{p}}_1-{\hat{p}}_2$ and its standard error, to three decimals.

In independent random samples, 121 of 220 swimmers and 81 of 180 runners stretch before practice. Find ${\hat{p}}_1-{\hat{p}}_2$ and its standard error, to three decimals.

A trial finds 60 of 200 patients on treatment A and 45 of 250 on treatment B improved. For $H_0:p_1=p_2$, find the pooled proportion and $z$, to two decimals.

Independent samples find 80 of 250 seniors and 54 of 300 juniors passed a driving test. For $H_0:p_1=p_2$, find the pooled proportion and $z$, to two decimals.

In independent samples, 35 of 100 online shoppers and 60 of 300 in-store shoppers used a coupon. For $H_0:p_1=p_2$, find the pooled proportion and $z$, to two decimals.

Independent samples find 45 of 150 east nurses and 20 of 100 west nurses renewed a certification. For $H_0:p_1=p_2$, find the pooled proportion and $z$, to two decimals.

Independent samples find 40 of 160 apartment residents and 70 of 200 dorm residents own a bike. For $H_0:p_1=p_2$, find the pooled proportion and $z$, to two decimals.

A survey took independent random samples: 80 of 200 east-campus students and 90 of 250 west-campus students had joined a club. A 95 percent confidence interval for $p_1-p_2$, east minus west, is $(-0.05,0.13)$. What does it support?

Independent random samples found 96 of 240 school students and 60 of 240 district students completed a summer course. A 95 percent interval for $p_1-p_2$, school minus district, is $(0.07,0.23)$. What does it support?

Independent samples found 50 of 200 clinic A patients and 84 of 240 clinic B patients used online check-in. A 95 percent interval for $p_1-p_2$, clinic A minus clinic B, is $(-0.19,-0.01)$. What conclusion is supported?

Independent random samples found 66 of 220 sophomores and 69 of 230 juniors rode the train to school. A 95 percent interval for $p_1-p_2$, sophomores minus juniors, is $(-0.08,0.08)$. What does it support?

Independent random samples found 150 of 300 north-side voters and 95 of 250 south-side voters favored a park bond. A 90 percent interval for $p_1-p_2$, north minus south, is $(0.05,0.19)$. What does it support?

Independent random samples include 24 of 80 male students and 18 of 90 female students who skip breakfast. To test whether the proportions differ, which setup fits a two-proportion z test?

Independent samples find 18 of 120 ninth graders and 8 of 100 tenth graders used a tutoring app. To test whether the proportions differ, which setup is appropriate?

Independent samples find 63 of 150 urban homes and 54 of 180 suburban homes compost food waste. To test whether the urban proportion is higher, which setup fits?

Independent samples find 12 of 200 line A parts and 24 of 160 line B parts are defective. To test whether line A's defect proportion is lower, which setup fits?

Independent random samples find 9 of 70 clinic A appointments and 18 of 90 clinic B appointments were rescheduled. To test whether the proportions differ, which setup fits?