In year 10, the table says the population is 25,000
But if we plugged x = 10 into the equation Lucy got, then,
y = 600x + 25000
y = 600(10) + 25000
y = 6000 + 25000
y = 31000
Lucy's equation says that the population in year x = 10 should be y = 31000 instead of 25000. So this is one way to show that there is an error. The output from the equation isn't matching what the table shows.
For large sample confidence intervals about the mean you have:
xBar ± z * sx / sqrt(n)
where xBar is the sample mean z is the zscore for having α% of the data in the tails, i.e., P( |Z| > z) = α sx is the sample standard deviation n is the sample size
We need only to concern ourselves with the error term of the CI, In order to find the sample size needed for a confidence interval of a given size.
z * sx / sqrt(n) = width.
so the z-score for the confidence interval of .98 is the value of z such that 0.01 is in each tail of the distribution. z = 2.326348
The equation we need to solve is:
z * sx / sqrt(n) = width
n = (z * sx / width) ^ 2.
n = ( 2.326348 * 6 / 3 ) ^ 2
n = 21.64758
Since n must be integer valued we need to take the ceiling of this solution.
n = 22
The answer is C) 160.
We know this because if mA = 50, we know that mC must also be 50. This is due to the fact that AB = BC. This leaves us with mB as 80 since the angles of a triangle always have to equal 180.
Now knowing this, it is easy to find the arc lengths in degrees. When you have a transcribed triangle, all we are going to do here is double the angle of the triangle to get the arc measure.
mB = 80
80*2 = 160
You can set up an system of equations
x=2y+8
x-y=25
Substitute x in to the second equation
2y+8-y=25
y+8=25
y=17
Substitute the y back in to the first equation.
x=2(17)+8=42
Answer:
Answer 1. 5 Answer 2. 60 Answer 3. 37
Step-by-step explanation:
