Step-by-step explanation:
In order to find the better buy, we must find the cheaper unit price or price per gallon. To find the price per gallon, divide the cost by the number of gallons.
Mary
Mary bought 4 gallons for $11.
The price is $11 and the gallons are 4.
Jill
Jill bought 2.5 gallons for $7.25
The price is $7.25 and the gallons are 2.5
Better buy
Mary paid $2.75 per gallon and Jill paid $2.90 per gallon. 2.75 is less than 2.90, so Mary had the better buy.
It is already simplified because 18 cant go into 25
Answer:
And the width for the confidence interval is given by:
And we want to see the effect if we increase the confidence level for a interval. On this case if we increase the confidence level then the critical value for the confidence interval 
would be higher and then the width of the interval would increase. So then the best answer for this case would be:
B. Increasing the level of confidence widens the interval.
Step-by-step explanation:
Let's assume that we have a parameter of interest 
who represent for example the true mean for a population. And we can construct a confidence interval in order to estimate this parameter if we know the distribution for the statistic let's say 
and for this particular example the confidence interval is given by:
Where ME represent the margin of error for the estimation and this margin of error is given by:
And the width for the confidence interval is given by:
And we want to see the effect if we increase the confidence level for a interval. On this case if we increase the confidence level then the critical value for the confidence interval would be higher and then the width of the interval would increase. So then the best answer for this case would be:
B. Increasing the level of confidence widens the interval.
Answer:
Last option (1/2)^3 = .125
Step-by-step explanation:
1/2 (1.035)^5 =0.579637
(2/3)^2 = 4/9 = .4444
.2^2/.3^2 = 0.04/0.09 = .44444
(1/2)^3 = 1/8 = .125
So we can clearly see the last one as the answer
