Question: It has been reported that 18 3 of all U S households
It has been reported that 18.3% of all U.S. households were heated by electricity in 1980, compared to 27.4% in 1995 and 31.5% in 2005. At the 0.05 level, and assuming a sample size of 1000 U.S. households for each year, test whether the population percentages could be equal for these years.
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