Question

From a circular card-sheet of radius 5 cm, a circular sheet of radius of 4 cm is removed. Find the area of the remaining sheet ( π = 3.14).

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Answer 1

Step-by-step explanation:

for big circle radius =R=5cm

area of the big circle=πr^2=πR^2

for small circle which will be removed radius=r=4cm

area of small circle=πr^2

hence, the area of remaining sheet when small circle will be removed from big one=area of big circle - area of small circle=πR^2-πr^2=π(R^2-r^2)=3.14(5^2-4^2)=3.14(25-16)=3.14(9)=3.14×9=28.26sq.cm

hence the area of remaining sheet is 28.26sq.cm

Answer 2

$\large{\bf{\red{\underline{\underline{AnsWer}}}}}$

Area of outer circle =$\pi {r}^{2} \\ = \frac{22}{7} \times 14 \times 14 \\ = 22 \times 28 = 616 cm²</p><p>⠀⠀⠀⠀</p><p>\\ \\ area \: of \: inner \: circle \: = 2 \times \pi {r}^{2} \\ \: = \: 2 \times \frac{22}{7} \times 35 \times 35 \\ = 22 \times 3.5 \\ = 77 {cm}^{2} \\ \\ </p><p>area \: of \: rectangle = \: l \times b \\ area</p><p> \: of \: whole \: circle \: -</p><p> \: ( \: area </p><p>\: of \: the</p><p> \: both \: circles \: </p><p>+ </p><p>\: area \: of</p><p> \: rectangle</p><p> \: ) \: = \: area </p><p>\: of</p><p> \: remaing \: sheet. \\ = 616 \: - \: ( \: 77 + 3) \\</p><p> = 616 - 80 = </p><p> {536cm}^{2} ....$