Question

Q21. From a circular sheet of radius 10 cm, a circle of radius 4cm is
removed. What is the area of remaining sheet? (
$\pi$
= 3.14). *​

Answer 1

Answer:

$\red\bigstar$ Area of the remaining sheet = 263.76 cm² ≈ 263.8 cm².

SOLUTION

Area of the circle of radius 10cm

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Area of a circle = πr²,Where 'r' is the radius.

⇒ Area of the circle of radius 10cm = π × 10²

⇒ Area of the circle of radius 10cm = 100 × π

⇒ Area of the circle of radius 10cm = 100π cm²

Area of the circle of radius 4cm

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Area of a circle = πr²,Where 'r' is the radius.

⇒ Area of the circle of radius 4cm = π × 4²

⇒ Area of the circle of radius 4cm = 16 × π

⇒ Area of the circle of radius 4cm = 16π cm².

$\boxed{\sf Area \: of \:the \:remaining \:sheet = Area \:of \:the \: circle \:of \:radius \:10cm - Area \:of \: the \:circle \:of \:radius \: 4cm}$

⇒ Area of the remaining sheet =  100π - 16π

 ⇒Area of the remaining sheet = 84π

 ⇒Area of the remaining sheet = 84 × 3.14

⇒ Area of the remaining sheet = 263.76 cm² ≈ 263.8 cm².

Answer 2

Answer:

Area of remaining sheet is 263.89 sq cm

Step-by-step explanation:

Given that

Radius of circular sheet is 10cm

Radius of circle is of 4cm

To find

Area of circle

Solution

As we know that

$area \: of \: circular sheet = \pi \times {radius}^{2}$

put

$\pi = 3.14$

now

$area \: of \: circular sheet = 3.14 \times {10}^{2}$

by multiplication we get

$area \: of \: area of circular sheet = 314.159 {cm}^{2}$

Now area of circle having radius 4 is

$area \: of \: circle = \pi \times {4}^{2}$

by multiplication we get

$area \: of \: circle = 50.26 {cm}^{2}$

We have to find area of remaining sheet when area of circle is removed hence

$area \: of \: remaining \: sheet = area \: of \: circular \: sheet - area \: of \: circle$

$area \: of \: remaining \: sheet = 314.159 - 50.26$

by subtraction we get

$area \: of \: remaining \: sheet = 263.89 {cm}^{2}$