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1 year ago

determine The length of the circular arc of a circle with a radius of 49 cm subtended by a central angle of 135°

Mathematics

1 answer:

Katena32 [7]1 year ago

6 0

Given:

Length of the circular arc with circle radius=49cm

θ=135°

Now,

Length of arc = θ/360°×2πr

49=2× 22/7×r×135°/360°

49×20×7/3×22×2

51.96cm

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Step-by-step explanation:

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Part a

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On this case we need to find the sample standard deviation with the following formula:

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The sample deviation for this case is s=30.23

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$\frac{(8)(30.23)^2}{20.09} \leq \sigma^2 \leq \frac{(8)(30.23)^2}{1.65}$

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Now we just take square root on both sides of the interval and we got:

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Part b

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To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal probability distribution

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