Answer:
Step-by-step explanation:
2pi
____
3
Answer:
C. The college spread is best described by the IQR. The high school spread is best described by the standard deviation.
Step-by-step explanation:
If data is normally distributed we use Standard deviation otherwise we use Interquartile Range (IQR) for measuring the spread.
Further, data is said to be normally distributed if Mean = Median = Mode.
So, High School data is normally distributed but College data is not.
So, We measure the spread of College data by IQR and High School data by Standard Deviation.
Thus, Option C is the only correct option.
Subtract 3 both sides first. R-3=ts²
next, divide both sides by t, (R-3)/t=s²
finally, take the square root of both sides
√(R-3)/t = s. 2nd choice.
Answer:
The environmentalist can be 90% confident that the true mean weight of all cars is between 2.8 and 3.4 tons.
Step-by-step explanation:
x% confidence interval:
A confidence interval is built from a sample, has bounds a and b, and has a confidence level of x%. It means that we are x% confident that the population mean is between a and b.
In this question:
90% confidence interval between 2.8 and 3.4 tons. This means that the environmentalist can be 90% sure that the mean weight of all cars is in this interval, that is:
The environmentalist can be 90% confident that the true mean weight of all cars is between 2.8 and 3.4 tons.
Answer:
130 N/cm2
Step-by-step explanation:
7.8 cm2 -> 50N/cm2
3 cm2 -> x N/cm2
x = (50×7.8) / 3
x = 130N/cm2