WEBVTT
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A wheel covers a distance of 4312 meters after 98 cycles.
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Using 22 over seven in place of đťś‹, find the wheelâ€™s diameter.
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The first thing that we need to do is to find the distance thatâ€™s been covered during one cycle.
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And we can do this by dividing the total distance by the number of cycles.
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So we divide 4312 by 98.
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And popping that into a calculator will give us a distance of 44 meters.
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The mathematical word that we use for the distance around the edge of a circle is the circumference.
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And since we know that the wheel has covered 44 meters in one cycle, then we can say that the circumference is 44 meters.
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To find the diameter, we can use the formula circumference equals đťś‹ times diameter.
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And we remember that the diameter of a circle is a line that passes from one side to the other through the center.
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Itâ€™s also equal to twice the radius.
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So we can substitute in our values for the circumference.
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And remembering that we can use 22 over seven for đťś‹.
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This will give us 44 equals 22 over seven times the diameter.
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In order to get the diameter by itself, we need to divide both sides for our equation by 22 over seven.
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This will give us 44 divided by 22 over seven equals the diameter.
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Annoyed to divide by this fraction, 22 over seven, we changed the division to a multiplication and flipped the numerator and denominator.
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Giving us a calculation 44 times seven over 22 for our diameter.
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We can simplify this calculation if we noticed that 44 has two lots of 22 in it.
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Which leaves us with the calculation of two times seven for our diameter.
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Therefore, the answer for the diameter is 14 meters.