Answer:
After 460 calls plan 1 is more economical than plan 2
Step-by-step explanation:
Plan 1: 36x + 0y
Plan 2: 13x + 0.05y
36x < 13x + 0.05y
36x - 13x < 0.05y
23x < 0.05y
23/0.05x < y
460x < y
Answer:
The 99% confidence interval for the fraction of U.S. adult Twitter users who get some news on Twitter is between 49.34% and 60.66%, which means that we are 99% sure that the true percentage of US adult Twitter users who get some news is in this interval.
Step-by-step explanation:
Confidence interval:
A confidence interval has the following format:

In which M is the sample mean, z is related to the confidence level and s is the standard error.
55% of U.S. adult Twitter users get at least some news on Twitter (Pew, 2013). The standard error for this estimate was 2.2%.
This means that 
99% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
Lower bound of the interval:
Upper bound:
The 99% confidence interval for the fraction of U.S. adult Twitter users who get some news on Twitter is between 49.34% and 60.66%, which means that we are 99% sure that the true percentage of US adult Twitter users who get some news is in this interval.
Answer:
<h2><u><em>
55°</em></u></h2>
Step-by-step explanation:
the sum of the interior angles of a triangles is 180°
so
180 = 75 + 50 + x
x = 180 - 75 - 50
x = 55°
-----------------------
check
55 + 75 + 50 = 180°
the answer is good
the answer is 87 60% or 145 = 87