Geometry

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Geometry

by Pawan Ramnani » Thu Sep 08, 2016 6:08 pm
If 20 circular pepperoni slices each with a 1 inch-diameter cover a circular pizza pie with diameter 14 inches, what fraction of the pizza is covered with pepperoni slices?

a)5/49
b)3/49
c)7/49
d)6/79
e)9/79

Answer is a.
Need help in solution.

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by MartyMurray » Thu Sep 08, 2016 7:15 pm
Fraction Of Area Of Pizza That Is Covered By Pepperoni = Total Area Of Pepperoni Slices/Total Area Of Pizza

Area Of One Pepperoni Slice = πr² = π(1/2)² = π/4

Area Of All 20 Pepperoni Slices = 20 * π/4 = 5π

Area Of Pizza = πr² = π7² = 49π

Fraction Of Area Of Pizza That Is Covered By Pepperoni = 5Ï€/49Ï€ = 5/49

The correct answer is A.
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by shounkdhir » Fri Sep 09, 2016 12:51 am
the answer is a

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by Matt@VeritasPrep » Thu Sep 15, 2016 9:24 pm
Slices / Pie =>

20 * ((half-diameter of slice)² * π) / ((half-diameter of pie)² * π)

20 * (.5² * π) / (7² * π) =>

20 * .25 * π / 49π =>

5/49