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Daniel has a circular piece of paper with a radius of 13 cm. He cuts a circular hole

with a radius of 5 cm in the centre of his piece of paper to make the shape shown
below.
Calculate the area of this shape.
Give your answer in cm² to 1 d.p.
13 cm
5 cm
Not drawn accurately

Daniel has a circular piece of paper with a radius of 13 cm. He cuts a circular hole-example-1
User GoodDok
by
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2 Answers

6 votes

Final answer:

To calculate the area of the shape, subtract the area of the smaller circle from the area of the larger circle using the formula A = πr². In this case, the radius of the larger circle is 13 cm and the radius of the smaller circle is 5 cm. Simplify the equation to find the area.

Step-by-step explanation:

To calculate the area of the shape, you need to find the area of the larger circle and subtract the area of the smaller circle that was cut out. The area of a circle is given by the formula A = πr², where r is the radius. For the larger circle, the radius is 13 cm, so the area is A = π(13 cm)². For the smaller circle, the radius is 5 cm, so the area is A = π(5 cm)². To find the area of the shape, subtract the area of the smaller circle from the area of the larger circle: A = π(13 cm)² - π(5 cm)².

Simplifying the equation gives us A = π(169 cm²) - π(25 cm²) = 144π cm² - 25π cm². This can be further simplified as A = 119π cm².

Now, we can substitute the approximate value of pi as 3.14 and calculate the area: A ≈ 119(3.14) cm² ≈ 373.66 cm².

User Christopher Barber
by
8.0k points
0 votes

Answer:

Step-by-step explanation: Area of circle = pi.r²

A= pi. 5²

A= pi. 25

A≈78cm²

User SBM
by
7.3k points