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)7/49
b)6/49
c)4/49
d)5/79
e)9/79
OA is d
why is option B considered to be wrong and A taken as the correct answer.
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Well, none of the options is correct. The correct answer is 5/49.Roland2rule wrote: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)7/49
b)6/49
c)4/49
d)5/79
e)9/79
OA is d
why is option B considered to be wrong and A taken as the correct answer.
Area of one piece of pepperoni slice = π∗(1/2)^2 = π/4
So, the area of 20 slides = 20∗π/4 = 5π
Area of the pizza = π∗7^2 = 49π
Fraction covered = 5Ï€/49Ï€ = 5/49
The correct answer: [spoiler]5/49[/spoiler]
Hope this helps!
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-Jay
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