I'd say option D because you can just tell right off the bat that if x = 0, then f(x) = 43.75.
Answer as an improper fraction = 16/5
Answer as a mixed number = 3 & 1/5
Answer in decimal form = 3.2
All of those values represent the same thing, but written in a different way.
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Explanation:
I'm assuming HM stands for Harmonic Mean in this case.
If so, then we apply the reciprocal operation to each value to get 1/2 and 1/8 (from 2 and 8 respectively).
Add up those fractions:
1/2 + 1/8 = 4/8 + 1/8 = 5/8
Now we'll divide n = 2 over that result. The n = 2 refers to the number of items in the original set.
n divide over (5/8) = 2*(8/5) = 16/5 which is the answer as an improper fraction
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To convert to a mixed number, we can do the following:
16/5 = (15+1)/5
16/5 = 15/5 + 1/5
16/5 = 3 + 1/5
16/5 = 3 & 1/5
Or if you need the answer in decimal form, then using a calculator would get you 16/5 = 3.2
According to the empirical rule, roughly 68% of the scores fall between z = -1 and z = 1
You can use a calculator to get a more approximate answer. If you have a TI calculator, you can use the "normalcdf" function to type in normalcdf(-1,1)
Easy
the easiest way is to imagine that you have a rectangle with a corner cut off
the area of the figure=area of rectangle-area cut off
area that was cut off was a triangle
area of rectangle=length times width
area of triangle=1/2base times height
so we draw imaginary lines like in attachment
find area of rectangle
legnth=9 inch
width=9 inch
area=9 times 9=81 in^2
triangle
the top part is ?+5=9, so the base of triangle=4
the side is ?+4=9, so the base is 5
area=1/2 times 4 times 5=10 in^2
area=rectangle-triangle
area=81-10=71 in^2
The is the correct answer x=80