Answer:
We need a sample size of least 119
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
The margin of error is:

95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
Sample size needed
At least n, in which n is found when 
We don't know the proportion, so we use
, which is when we would need the largest sample size.






Rounding up
We need a sample size of least 119
Answer:
cos-1 (6.3/9.8).
sin-1(7.5/9.8).
Step-by-step explanation:
cos < ABC = 6.3/9.8.
sin < ABC = 7.5/9.8.
<span>f(x) is the function that models Peters total video game time.
</span><span>Peter played his favorite video game for 10 hours last week.
</span><span>Peters parents restricted him to 5 additional hours each week for the next 8 weeks.
After 8 weeks Peter will have played f(x) hours video game.
f(x)=10+8*x , where x is the number of hours Peter plays every week and this number is smaller than 5 (his parents restricted this number) , x<5
</span>
Ok, so the starting numbers are the fixed amounts. If we think of a graph, this is the y-intercept/ starting point and the rate would continue from there. This conclusion is very important to writing a linear equation in slope-intercept form.
If you don’t remember, slope-intercept form is y=mx+b, where m is the slope and b is the y-intercept.
First, let’s make our equations.....
Plan A: y = 0.07x + 26
Plan B: y = 0.12x + 17
Now since it is not stated, I’m not sure if you need to find where the cost of both plans is equal, but that would be found by setting up a system of equations and using substitution.
y = 0.07x + 26
y = 0.12x + 17
Substitute one equation into the other...
0.07x + 26 = 0.12x + 17
- 0.05x = -9
0.05x = 9
x = 180
And there you have it! After 180 minutes [3 hours] of talking, both phone plans will have the same cost.