Answer:
The fraction of the students who failed to went partying = 
Step-by-step explanation:
Let total number of students = 100
No. of students partied are twice the no. of students who not partied.
⇒ No. of students partied = 2 × the no. of students who are not partied
No. of students partied before the exam = 20 % of total students
⇒ No. of students partied before the exam =
× 100
⇒ No. of students partied before the exam = 20
No. of students who not partied before the exam = 
Thus the fraction of the students who failed to went partying = 
Use the Pythagorean theorem since you are working with a right triangle:
a^2+b^2=c^2a2+b2=c2
The legs are a and b and the hypotenuse is c. The hypotenuse is always opposite the 90° angle. Insert the appropriate values:
0.8^2+0.6^2=c^20.82+0.62=c2
Solve for c. Simplify the exponents (x^2=x*xx2=x∗x ):
0.64+0.36=c^20.64+0.36=c2
Add:
1=c^21=c2
Isolate c. Find the square root of both sides:
\begin{gathered}\sqrt{1}=\sqrt{c^2}\\\\\sqrt{1}=c\end{gathered}1=c21=c
Simplify \sqrt{1}1 . Any root of 1 is 1:
c=c= ±11 *
c=1,-1c=1,−1
Answer:
(0.46, 0.52)
Step-by-step explanation:
The formula for Confidence Interval with Proportion
CI = p ± z × √p(1 - p)/n
Where
p = Proportion = x/n
x = 346
n = 706
p = 346/706
p = 0.49
z = z score of Confidence Interval 90% = 1.645
Therefore:
CI = 0.49 ± 1.645 × √0.49(1 - 0.49)/706
CI = 0.49 ± 1.645 × √0.49 × 0.51/706
CI = 0.49 ± 1.645 × 0.0188139843
CI = 0.49 ± 0.0309490042
Hence:
Confidence Interval is
0.49 - 0.0309490042
= 0.4590509958
≈ 0.46
0.49 + 0.0309490042
= 0.5209490042
≈ 0.52
Therefore , the confidence interval of the population proportion is
(0.46, 0.52)
Rounded up the first quarter sales average would be 24,518. If you write it all out it would be 24,517.6667