The answer is 8i.
i = √(-1)
√(-64) = √((-1) * 64)
= √(-1) * √64
= i * √8²
= i * 8
= 8i
Answer:
The 95% confidence interval for the proportion of students who get coaching on the SAT is (0.1232, 0.147).
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 z-score that has a p-value of
.
427 had paid for coaching courses and the remaining 2733 had not.
This means that 
95% confidence level
So
, z is the value of Z that has a p-value of
, so
.
The lower limit of this interval is:

The upper limit of this interval is:

The 95% confidence interval for the proportion of students who get coaching on the SAT is (0.1232, 0.147).
Answer:
7 cm²
Step-by-step explanation:
Area of a triangle = (Base * hight) / 2
A = (2* 7) /2 = 14/ 2 = 7 cm²
Divide both sides by 2.
2/5
:)