Hello! i can do the first word problem
first we need to divide 600/3 which is 200.
therefore we can infer that he does 200 letters an hour and we can solve the problem with this
200 x 7 = 1400 letters an hour
Answer:
No
Step-by-step explanation:
Plug (-2,1) into -3x+y=5. This will make it -3(-2)+(1)=5. This is equal to 6+1=5. 7=5. 7 is not equal to 5. Therefore, (-2,1) is not a solution to the equation -3x+y=5.
If this helps please mark as brainliest
Answer:
a. n=4148
b. n=3909
c. The sample size is smaller if a known proportion from prior study is used. The difference in sample sizes is 239
Step-by-step explanation:
a. For sample where no preliminary estimate is given, the minimum sample size is calculated using the formula:

Where:
Margin of error
is the assumed proportion
#Let p=0.5, substitute in the formula to solve for n:

Hence, the minimum sample size is 4148
b. If given a preliminary estimate p=0.38, we use the same formula but substitute p with the given value:

Hence, the minimum sample size is 3909
c. Comparing the sample sizes from a and b:

Hence, the actual sample size is smaller for a known proportion from prior a prior study.
Answer:
Step-by-step explanation:
So 8 times what is 5?
8 times x=5
x=0.625
Answer:
The standard deviation of the sample mean differences is _5.23_
Step-by-step explanation:
We have a sample of a population A and a sample of a population B.
For the sample of population A, the standard deviation
is

The sample size
is:
.
For the sample of population B, the standard deviation
is

The sample size
is:
.
Then the standard deviation for the difference of means has the following form:

Finally
