https://artofproblemsolving.com/wiki/api.php?action=feedcontributions&user=Diyap10&feedformat=atomAoPS Wiki - User contributions [en]2021-08-04T23:40:42ZUser contributionsMediaWiki 1.31.1https://artofproblemsolving.com/wiki/index.php?title=1953_AHSME_Problems/Problem_11&diff=1193471953 AHSME Problems/Problem 112020-03-13T23:13:28Z<p>Diyap10: /* Problem */</p>
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<div>A running track is the ring formed by two concentric circles. If the circumferences of the two circles differ by <math>10\pi </math> feet, how wide is the track in feet?<br />
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== Solution ==<br />
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We notice that since the running track is simply the area of the outer circle that is outside of the inner circle, the radius of the larger circle must be precisely <math>10</math> feet larger than the radius of the smaller circle. <br />
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Since the circumference of a circle is calculated as <math>2\pi{r}</math> where <math>r</math> is the radius, we know that the circumference of the smaller circle is <math>2\pi{r}</math> and the circumference of the larger circle is <math>2\pi(r+10)=2\pi{r}+20\pi</math>. <br />
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The difference between the circumferences is <math>2\pi{r}+20\pi-2\pi{r}=20\pi\approx20\cdot3=\boxed{\textbf{(C) } 60\text{ feet}}</math>.<br />
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==See Also==<br />
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{{AHSME 50p box|year=1953|num-b=10|num-a=12}}<br />
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[[Category:Introductory Algebra Problems]]<br />
{{MAA Notice}}</div>Diyap10https://artofproblemsolving.com/wiki/index.php?title=The_figure_shows_a_square_of_side_$y$_units_divided_into_a_square_of_side_$x$_units_and_four_congruent_rectangles._What_is_the_perimeter,_in_units,_of_one_of_the_four_congruent_rectangles%3F_Express_your_answer_in_terms_of_$y$.&diff=118783The figure shows a square of side $y$ units divided into a square of side $x$ units and four congruent rectangles. What is the perimeter, in units, of one of the four congruent rectangles? Express your answer in terms of $y$.2020-03-05T02:13:42Z<p>Diyap10: Created blank page</p>
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<div></div>Diyap10https://artofproblemsolving.com/wiki/index.php?title=A_stock_loses_$10%5C%25$_of_its_value_on_Monday._On_Tuesday_it_loses_$20%5C%25$_of_the_value_it_had_at_the_end_of_the_day_on_Monday._What_is_the_overall_percent_loss_in_value_from_the_beginning_of_Monday_to_the_end_of_Tuesday%3F_Enter_the_answer_as_a_percent.&diff=118319A stock loses $10\%$ of its value on Monday. On Tuesday it loses $20\%$ of the value it had at the end of the day on Monday. What is the overall percent loss in value from the beginning of Monday to the end of Tuesday? Enter the answer as a percent.2020-02-23T15:31:06Z<p>Diyap10: Created blank page</p>
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