-b/2a is the axis of symmetry formula.
To solve those 4 questions, find the values of a and b (coefficients of ax^2 and bx term) and substitute them into the formula.
Hope this helps!
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
(+/-) <span>1 x (+/-) 232 = 232
</span>(+/-) <span>2 x (+/-)116 = 232
</span>(+/-) 4 x (+/-) <span>58 = 232
</span>(+/-) 8 x (+/-) <span>29 = 232
</span>(+/-) 29 x (+/-) <span>8 = 232
</span>(+/-) 58 x (+/-) <span>4 = 232
</span>(+/-) 116 x (+/-) <span>2 = 232
</span>(+/-) 232 x (+/-) 1 = 232
Answer:
It is $42
if I am wrong then let me know so I can recheck my work
