Answer:
The sample proportion represents a statistically significant difference from 50%
Step-by-step explanation:
Null hypothesis: The sample proportion is the same as 50%
Alternate hypothesis: The sample proportion is not the same as 50%
z = (p' - p) ÷ sqrt[p(1 - p) ÷ n]
p' is sample proportion = 289/400 = 0.7225
p is population proportion = 50% = 0.5
n is number of students sampled = 400
z = (0.7225 - 0.5) ÷ sqrt[0.5(1 - 0.5) ÷ 400] = 0.2225 ÷ 0.025 = 8.9
The test is a two-tailed test. Using a 0.01 significance level, critical value is 2.576. The region of no rejection of the null hypothesis is -2.576 and 2.576.
Conclusion:
Reject the null hypothesis because the test statistic 8.9 falls outside the region bounded by the critical values -2.576 and 2.576.
There is sufficient evidence to conclude that the sample proportion represents a statistically significant difference from 50%.
<span>Watching television and reading newspaper are not independent events because P(A|B)=P(A) and P(B|A)=P(B) .
I might be wrong so try to look at it a little closer before you take my word for it.
</span>
I wish I could say it to you but I don't know how to plan it
Answer:19.74 gallons of the gas in the tank is wasted.
Step-by-step explanation:
Since the efficiency of the gas engine is 6%, wastage is #= 100 - 6 = 94%.
Therefore wastage = 94% x 21=94 x21/100=19.74 gallons
