Answer:
a) P(X<50)=0.9827
b) P(X>47)=0.4321
c) P(-1.5<z<1.5)=0.8664
Step-by-step explanation:
We will calculate the probability based on a random sample of one moped out of the population, normally distributed with mean 46.7 and standard deviation 1.75.
a) This means we have to calculate P(x<50).
We will calculate the z-score and then calculate the probability accordign to the standard normal distribution:

b) We have to calculatee P(x>47).
We will calculate the z-score and then calculate the probability accordign to the standard normal distribution:

c) If the value differs 1.5 standard deviations from the mean value, we have a z-score of z=1.5

So the probability that maximum speed differs from the mean value by at most 1.5 standard deviations is P(-1.5<z<1.5):

Answer:
24x^2+112x+120
Step-by-step explanation:
distribute the 2
(6x+10)(4x+12)
foil it
24x^2+112x+120
Answer:
484 feet maximum
Step-by-step explanation:
H(t)=-16t^2+112t+288
The maximum height occurs at the vertex of this graph.
Let us find the vertex.
vertex x-coordinate = -b/2a
x = -b/2a = -(112)/ (2*-16) = 7/2 sec.
H(7/2) = - 16 *(7/2)^2 + 112*(7/2) + 288
H(7/2) = -196 + 392 + 288 = 484 feet ..
<em>Answer: h = 120 ft; w = 80 ft </em>
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<em>A = 9600 ft^2</em>
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<em>Step-by-step explanation: Let h and w be the dimensions of the playground. The area is given by:</em>
<em></em>
<em>A = h*w (eq1)</em>
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<em>The total amount of fence used is:</em>
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<em>L = 2*h + 2*w + w (eq2) (an extra distance w beacuse of the division)</em>
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<em>Solving for w:</em>
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<em>w = L - 2/3*h = 480 - 2/3*h (eq3) Replacing this into the area eq:</em>
<em></em>
<em></em>
<em></em>
<em>We derive this and equal zero to find its maximum:</em>
<em></em>
<em> Solving for h:</em>
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<em>h = 120 ft. Replacing this into eq3:</em>
<em></em>
<em>w = 80ft</em>
<em></em>
<em>Therefore the maximum area is:</em>
<em></em>
<em>A = 9600 ft^2</em>
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