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Can u guys PLEASE answer this question ASAP. THIS IS EXTREMELY URGENT. Twenty circular pieces of pastry, each of diameter 4 cm, are cut from a rectangular layer of pastry 20 cm long and 16 cm wide. What is the area, correct to two decimal places, of pastry remaining after the 20 pieces are removed?

User TheAgent
by
5.3k points

1 Answer

2 votes

Answer:

68,67 cm^2

Explanation:

Let's calculate first the total area of pastry that we have.

Let A be that area.

The pastry has rectangular form so its area is:

● A = width × length

The width here is 16 and the length is 20

● A = 20 × 16

● A = 320 cm^2

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Let's calculate the are of the 20 pastry circles

Let A' be the area of one circle.

● A' = Pi × r^2

r is the radius wich is the diameter over 2.

● d/2 = 4/2 = 2 cm

● A' = Pi × 2^2

● A' = 4Pi cm^2

The area of 20 pastry circles is 20A'

● 20A'= 20 × 4 × Pi

● 20A'= 80Pi

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Let A" be the area of the remaining pastry

● A" = A-20A'

● A" = 320 - 80Pi

● A" = 68.67 cm^2

User Colt
by
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