Z-scores are expressed in terms of standard deviations from their means. <span>The standard score is simply the score, minus the mean score, divided by the standard deviation. It is calculated as follows:
z = X- mean / standard deviation
z = 2.7 - 2.4 / 1.5
z = 0.2</span>
Fun, geometry disguised as probability.
That's a pentagon, which we can view as 10 right triangles with legs a and s/2 (half of s) and hypotenuse r. So area of the pentagon is
P = 10 × (1/2) a (s/2) = 10 (1/2) (3.2) (4.7/2) = 37.6
The area of the circle is πr² so the circle area is
C = π (4²) = 50.265482
The white area is the difference, C-P, and the probability we seek is the fraction of the circle that's white, so (C-P)/C.
p = (C-P)/C =1-P/C = 1-37.6/50.265482 = 0.251971
Answer: 0.25
Higher than I would have guessed from the figure.
I'll do problem 1 to get you started.
The vertical sides are 3 and x for the left and right figures.
The horizontal sides are 15 and 60 for the left and right figures.
The corresponding sides form fractions which are equal (due to the nature of the similar polygons)
3/x = 15/60
3*60 = x*15 ... cross multiply
180 = 15x
15x = 180
x = 180/15 .... divide both sides by 15
x = 12
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Another way you can see this is note how the jump from 15 to 60 is "times 4", so the jump from 3 to x must also be "times 4" to keep the same proportion
3 ---> x = 3*4 = 12
Or you could set up the proportion
60/15 = x/3
4 = x/3
x/3 = 4
x = 3*4
x = 12
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<h3>Final Answer: 12</h3>
10=1+9 1x9=9
=2+8 2x8=16
=3+7 3x7=21
=4+6 4x6=24
=5+5 5x5=25
↑ Left: the possible measurements of the two fences, Right: the possible areas
out of the areas calculated, 25 sq feet is the maximum. :)
Ans: 25 square feet
