Question

Directions:  Show all work including steps used during computations using formulas and diagrams when appropriate.  Write a DETAILED statement explaining the meaning of your computations (conclusions) for all problems- hypothesis tests and confidence intervals.  Remember that the conclusions for hypothesis tests need both a statement about the null and alternative hypotheses and another sentence or two describing how that applies specifically to the context given in the question.

1. A recent poll of 500 registered Democrats found that 315 of them worry a great deal about the environment.  
(a)  Make a 95% confidence interval for the proportion of all Democrats who think that climate change is a serious problem.
(b)  In the same poll (at Gallop.org), 20% of Republicans surveyed worry a great deal about the environment.  Is that value significantly different from the statistic reported for Democrats?  Explain mathematically.

Answer 1

,-we have given SD D n,

0.2 O Test &tatish'co SO D

0.43 σ.42 Hes vaue is sijnificntli different Ham the Sahsh'ct