Hypothesis Testing Confusion with Significance Levels

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I need help in setting both of these up. I am confused on how to do significance levels in my problems. We are currently studying Hypothesis Testing and sorts. TIA!


20)In December 2001, 38% of adults with children under the age of 18 reported that their family ate dinner together 7 nights a week. In a recent poll, 403 of 1122 adults with children under the age of 18 reported that their family ate dinner together 7 nights a week. Has the proportion of families with children under the age of 18 who eat dinner together 7 nights a week decreased? Use the a=0.05 significance level.

22)In 2000, 58% of females aged 15 years of age and older lived alone, according to the U.S Census Bureau. A sociologist tests whether this percentage is different today by conducting a random sample of 500 females aged 15 years of age and older and finds that 285 are living alone. Is there sufficient evidence at the a=0.1 level of significance to conclude the proportion has changed since 2000?