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sertanlavr [38]

3 years ago

13

A running track in the shape of an oval is shown. The ends of the track form semicircles. A running track is shown. The left and

right edges of the track are identical curves. The top and bottom edges of the track are straight lines. The track has width 68 m and length of one straight edge 140 m. What is the perimeter of the inside of the track?

2 answers:

Minchanka [31]3 years ago

5 0

Two shapes.. a circle and a rectangle. The width of the rectangle serves as the diameter of the circle.

Length = 140 m ; Width = 68 m

Circumference of a circle = 2 π r
circumference of a cirlce = 2 * 3.14 * (68m/2) = 2 * 3.14 * 34 m = 213.52

length = 2 * 140 m = 280 m

perimeter of the oval = 213.52 m + 280 m = 493.52 m

ad-work [718]3 years ago

3 0

Answer:

493.52

Step-by-step explanation:

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vovangra [49]

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3 years ago

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Bad White [126]

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Step-by-step explanation:

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3 years ago

A random sample of 60 suspension helmets used by motorcycle riders and automobile race-car drivers was subjected to an impact te

pentagon [3]

Answer:

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Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

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For this problem, we have that:

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$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.283 - 1.96\sqrt{\frac{0.283*0.717}{60}} = 0.169$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.283 + 1.96\sqrt{\frac{0.283*0.717}{60}} = 0.397$

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3 years ago

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3 years ago

It's been estimated that if you consume an extra 3,500 calories, you will gain 1 pound of fat. one can of soda contains 40 grams

timama [110]

We know that
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if 1 gram sugar------------------------------------>has 4 calories
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</span><span>six-pack of soda every day--------------> 6*160=960 calories every day

in one year------------> 960*365=350400 calories in one year

if 3500 calories----------------> </span><span>1 pound of fat
</span>350400 calories----------------X
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