Answer:
68% of the sample can be expected to fall between 28 and 32 cm
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 30
Standard deviation = 2
What proportion of the sample can be expected to fall between 28 and 32 cm
28 = 30-2
28 is one standard deviation below the mean
32 = 30 + 2
32 is one standard deviation above the mean
By the Empirical Rule, 68% of the sample can be expected to fall between 28 and 32 cm
If the question is to find the slope-intercept form of both lines, here's the answer:
Both lines pass through the point (-3,-4), so we can use these coordinates in both equations. The slope-intercept form is represented by y=mx+b, with m the slope, b the intersection of the line with Y'Y for x=0, y and x the coordinates of a point.
Let's first apply all these for the first line, with a slope of 4.
y = mx + b
y=-3; x=-4; m=4. All we need to do is find b.
-3 = 4(-4) + b
-3 = -16 + b
b=13
So the equation of the first line is y= 4x + 13.
Now, we'll do the same thing but for the second line:
y=-3; x=-4; m=-1/4, and we need to find b.
-3 = (-1/4)(-4) + b
-3 = 1 + b
b= -4
So the equation of the second line is y=(-1/4)x - 4
Hope this Helps! :)
I believe the answer would be B