Answer:
E. The sample size is the same for X and Y, and the confidence level used for the interval constructed from X is greater than the confidence level used for the interval constructed from Y
Step-by-step explanation:
Confidence interval formula is given as
CI = \bar{x} \pm z*(\sigma/\sqrt{n})
Here, we can see that the width of confidence interval is z*(\sigma/\sqrt{n}) , which is dependent only on z critical value, standard deviation (sigma) and sample size (n)
This simply entails that either z or n or both are greater for x as compared to y.
Option E is correct answer because x and y can have sample sizes, but if the z critical is greater for x, then the width will be larger.
White sheep: 162 black sheep: 18
Numbers are a ratio of 9: 1, total 10 parts
180/10 =18
18 x 9 =162 18 x 1 =18
Answer: she would pay $1386
Step-by-step explanation:
Let x represent the cost of an adult ticket.
Let y represent the cost of a child ticket.
He spent $882 on all of their tickets; 2 adult tickets and 3 child tickets. This means that
2x + 3y = 882 - - - - - - - - - - 1
Each adult ticket costs twice as much as each child ticket. This means that
x = 2y
Substituting x = 2y into equation 1, it becomes
2 × 2y + 3y = 882
4y + 3y = 882
7y = 882
y = 882/7 = 126
x = 2y = 126 × 2
x = 252
Each adult ticket costs $252 and each child ticket cost $126
If Mrs. Smith bought 4 adult tickets and 3 child tickets, the amount of money that she would have to pay is
252 × 4 + 126 × 3
= $1386
Rememer you can do anything to an equaiton as long as you do it to both sides
get x by itself
2x+5=19
minus 5 from both sides
2x+5-5=19-5
2x+0=14
2x=14
divide both sides by 2
2x/2=14/2
1x=7
x=7