Answer:
2 3/8 in.
Step-by-step explanation:

Answer:
5/6x + 3 = y
Step-by-step explanation:
The slope intercept form is:
mx + b = y
The slope is 5/6.
The y intercept is 3.
121 is big enough to assume normality and not worry about the t distribution. By the 68-95-99.7 rule a 95% confidence interval includes plus or minus two standard deviations. So 95% of the cars will be in the mph range

The question is a bit vague, but it seems we're being asked for the 95% confidence interval on the average of 121 cars. The 121 is a hint of course.
The standard deviation of the average is in general the standard deviation of the individual samples divided by the square root of n:

So repeating our experiment of taking the average 121 cars over and over, we expect 95% of the averages to be in the mph range

That's probably the answer they're looking for.
Answer:
6x+19
Step-by-step explanation:
First thing first, we need to multiply the 6 into the equation. We do this by multiplying the x and 2 by 6.
6(x+2)+7
Multiply
6x+12+7
Now we need to combine like terms by adding the 12 and 7
6x+19
There it is simplified.