Answer:
3. Standard deviation is the square root of the variance.
4. Standard deviation is useful because it has the same units as the underlying data.
Step-by-step explanation:
3. In statistics, the dispersion in a given data with respect to its mean distribution can be determined or measured by standard deviation and variance. The standard deviation of a distribution can also be determined as the square root of variance.
4. Standard deviation is measured in the same units as that of the original data. Thus it has the same units as the underlying data.
Alice should pick the enlarged-photo with dimensions of 8-inch by 10-inch.
Step-by-step explanation:
Step 1:
In order for a part of the photo to not be cut off, the enlarged photo's dimensions should be of a constant ratio with the original photo's dimensions.
We divide the dimensions of the enlarged-photo with the dimensions of the original photo to check which has a constant ratio.
Step 2:
The original photo was a 4-inch by 5-inch photo.
Option 1 is 7-inch by 9-inch, so the ratios are
The ratios are different so this cannot be the enlarged photo's dimensions.
Option 2 is 8-inch by 10-inch, so the ratios are
The ratios are the same so this can be the enlarged photo's dimensions.
Option 3 is 12-inch by 16-inch, so the ratios are
The ratios are different so this cannot be the enlarged photo's dimensions.
So the enlarged-photo with dimensions of 8-inch by 10-inch should be picked.
Answer:
y = 0
Step-by-step explanation:
Since there is no indication of a shift in the graph of f(x) = 3cos(-0.25x), then the midline must be the normal midline for a cosine or sine function which is: y = 0.
Answer:
c is correct answer for you
Answer:
269
Step-by-step explanation:
The margin of Error is E = 0.05
The level of significance is, α = 1 - confidence level = 1 - 0.9 = 0.1
Assume that the proportion is, p =0.5
From the standard normal table, observe that the critical value of Z for two tail test and 10% level of significance is 1.64
The calculation of sample size is as follows: n = (Z/E)²p(1-p)
n = (1.64/0.05)²0.5 (1 - 0.5)
n = (1.64/0.05)² 0.25
n = 1075.84 × 0.25
n = 268.96 ≈ 269
The required sample size with the given margin of error approximately is 269. This value indicates the size of the customers who are using this company’s products.