The required sample size is 694.
Given a student wants to make a guess within 0.03 of the true ratio with a 95% confidence level.
Margin of Error, E = 0.03
significance level α=0.05 {95% confidence}
A given estimate of the percentage of population p is p = 0.79.
The critical value for the significance level α = 0.05 is Zc = 1.96. This can be determined using either Excel or a normal probability table.
Use the following formula to calculate the minimum sample size required to estimate the percentage of population p within the required margin of error.
n≥p(1-p)(Zc÷E)²
n=0.796×(1-0.796)(1.96÷0.03)²
n=693.1016
Therefore, the resample sizequired to meet the condition is n ≥ 693.1016 and must be an integer. From this, we conclude that the minimum sample size required is n = 694.
Learn more about confidence level from here brainly.com/question/23630128
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The net change would be 60%.
Hope this helps! <3
Sophia
Answer:
CD = 6.385 units
Step-by-step explanation:
Given triangle ABC with right angle at C.
And AB = AD + 6 .
Now, consider the triangle ABC.
⇒ cos(∠BAC) = 
(cosФ = adj/hyp)
cos(20) = .
0.9397 = 
(since AB = AD + 6 and AC = AD + CD)
⇒ 0.9397 AD + 5.6382 = AD + CD
⇒ CD = 0.0603 AD + 5.6382. →→→→→ (1)
⇒ sin(∠BAC) = 
(sinФ = opp/hyp)
sin(20) = .
⇒ BC = AB sin(20) . →→→→→(2)
Now, consider the triangle BCD,
sin(∠BDC) = 
⇒ sin(80) =
CD = 
From (2), CD = 
.
⇒ CD = AB (0.3473)
⇒ CD = (AD + 6) (0.3473)
⇒ CD = 0.3473 AD + 2.0838 →→→→→→(3)
Now, (1) →→ CD = 0.0603 AD + 5.6382
(3) →→ CD = 0.3473 AD + 2.0838
⇒ 0.0603 AD + 5.6382 = 0.3473 AD + 2.0838
0.287 AD = 3.5544.
⇒ AD = 12.3847
⇒ From (1), CD = 0.0603(12.3847) + 5.6382
⇒ CD = 6.385 units
Height of a trapezoid:
h = 5 · sin 80° = 5 · 0.985 = 4.924
x = 5 · cos 80° = 5 · 0.17365 = 0.868
7 - x = 7 - 0.868 = 6.132
By the Pythagorean theorem:
d² = 6.132² + 4.924²
d² = 37.6 + 24.25
d² = 61.85
d = √61.85
d = 7.86 ≈ 8
Answer: The length of a diagonal brace is 8 feet.
A
C
D
F
G
Pretty sure those are all the answers, lmk:)
