Answer:
z = 1.960
Step-by-step explanation:
The sample proportion is:
p = 715 / 2684 = 0.2664
The standard error is:
σ = √(pq/n)
σ = √(0.266 × 0.734 / 2684)
σ = 0.0085
For α = 0.05, the confidence level is 95%. The z-statistic at 95% confidence is 1.960.
The margin of error is 1.960 × 0.0085 = 0.0167.
The confidence interval is 0.2664 ± 0.0167 = (0.2497, 0.2831).
The upper limit is 28.3%, so the journal can conclude with 95% confidence that the true percentage is less than 29%.
Answer:
y = negative (2) Superscript x Baseline + 3
Step-by-step explanation:
An exponential function has a range of y > 0. In order for it to have a range of y < 3, it must be reflected across the x-axis (given a negative multiplier) and must be translated upward 3 units.
That is, for some exponential function y = b^x, you must have something of the form ...
y = -a·b^x +3
Only one answer choice has this form:
Answer: First option 13
Solution
If ABCD is a rhombus, the diagonals must be perpendicular, then the angle (5x+25)° must be a right angle (90°):
(5x+25)°=90°
5x+25=90
Solving for x: Subtracting 25 both sides of the equation:
5x+25-25=90-25
Subtracting:
5x=65
Dividing both sides of the equation by 5:
5x/5=65/5
Dividing:
x=13
Answer: The value of x must be 13
