<span>Last
year, the average math SAT score for students at one school was 475. The
headmaster then introduced a new teaching method hoping to improve scores. This
year, the mean math SAT score for a sample of students was 491. The headmaster
concluded that the new teaching method produces higher SAT scores. The problem
with reporting results this way is voluntary response. The information of how
the teaching method isnot mentioned.</span>
Answer: y= -3/2x + 2
y= -3/2 + b
5 = -3/2 * -2 + b
5 = 3 + b
2 = b
Given: f(x)=(2x-2)/4
find f^-1(3)?
we need to find the inverse of f(x), so
x=(2y-2)/4
2y-2=4x
y-1=2x
y=2x+1
so, then f^-1(x)=2x+1
f^-1(3)=2(3)+1
=6+1
=7
so, the answer is 7
Answer:
We conclude that the population mean is 24.
Step-by-step explanation:
We are given the following in the question:
Population mean, μ = 24
Sample mean,
= 22.8
Sample size, n = 100
Alpha, α = 0.05
Sample standard deviation, s = 8.3
First, we design the null and the alternate hypothesis
We use Two-tailed z test to perform this hypothesis.
Formula:
Putting all the values, we have
We calculate the p-value with the help of standard z table.
P-value = 0.1498
Since the p-value is greater than the significance level, we accept the null hypothesis. The population mean is 24.
Now,
Since, the z-statistic lies in the acceptance region which is from -1.96 to +1.96, we accept the null hypothesis and conclude that the population mean is 24.