Answer:
The minimum sample size required to construct a 95% confidence interval for the population mean is 65.
Step-by-step explanation:
We are given the following in the question:
Population standard deviation,

We need to construct a 95% confidence interval such that the estimate is within 0.75 milligrams of the population mean.
Thus, the margin of error must me 0.75
Formula for margin of error:


Putting values, we get,

Thus, the minimum sample size required to construct a 95% confidence interval for the population mean is 65.
Answer:
BEC = C. 50
BCD = A. 120
Step-by-step explanation:
BEC
65 + 65 = 130
180 - 130 = 50
BCD = 180 - 60 = 120
BEC is 50
Answer:
Step-by-step explanation:
y = x - 1/4
x = 1/4 Put this value in for x
y = 1/4 - 1/4
y = 0
x = 13/4
y = 13/4 - 1/4 The denominators remain the same The numerators are subtracted.
y = (13 - 1)/4
y = 12/4
y = 3
If x is to = 2 then it must be changed so it's denominator is 4
2 = 8/4
y= 8/4 - 1/4
y = 7/4 or 1.75 or 1 3/4
Each smaller donation was for $20 The largest donation was $15 greater than the smaller donation. First, determine the size of each donation. Since they are in a ratio of 4:4:7, it's easiest to add the ratios together (4+4+7) = 15. Then divide the total donation by that sum (75/15) = 5. Finally, multiply 5 by each of the ratios. 5 * 4 = 20, 5 * 4 = 20, and 5 * 7 = 35 So the 2 smaller donations were $20 each, and the largest donation was for $35. The largest donation was $35 - $20 = $15 larger than one of the smaller donations.
Since this is a triangle all the angles within the triangle add up to 180 degrees so....
82+(9x+2)+(7x)=180
82+2+16x=180
16x+84=180
16x=96
X=6
If we plug in X to angle(9x+2) and angle (7x) we will get 56 and 42. We can get angle 2 by subtracting 180-42 which is 138
FINAL ANSWER: 138 degrees