Answer:
y= -1x + 2
Step-by-step explanation:
-4/4 is the same as saying -1. slope always has to be in the simplest form.
Answer:

Step-by-step explanation:
To find x, the following equation is generated given the available information:



Cross multiply


Collect like terms



Answer:
The standard error of the mean is 4.5.
Step-by-step explanation:
As we don't know the standard deviation of the population, we can estimate the standard error of the mean from the standard deviation of the sample as:

The sample is [30mins, 40 mins, 60 mins, 80 mins, 20 mins, 85 mins]. The size of the sample is n=6.
The mean of the sample is:

The standard deviation of the sample is calculated as:

Then, we can calculate the standard error of the mean as:

facotr -9
add factors
-1+9=8
correct