Question

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?

Answer 1

Answer:

68,67 cm^2

Step-by-step 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