Answer :

Area between two consecutive ribs

= \(\frac{1}{8}^{th} \) times the Total Area of the umbrella

\( = \ \frac{1}{8} \ × \pi r^2 \) ,where \( r \ = \ 45 \)cm

\( = \ \frac{1}{8} \ × \ \frac{22}{7} \ × \ (45)^2 \ = \ \frac{22275}{28} \) cm^{2}

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- Find the area of a quadrant of a circle whose circumference is 22 cm.
- The length of the minute hand of a clock is 14 cm. Find the area swept by the minute hand in 5 minutes.
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- To warn ships for underwater rocks a lighthouse spreads a red coloured light over a sector of angle 80º to a distance of 16.5 km. Find the area of the sea over which the ships are warned. (Use \( \pi \ = \ 3.14 \) )
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- Tick the correct answer in the following : Area of a sector of angle p (in degrees) of a circle with radius R is : (a) \( \frac{p}{180} \ × \ 2\pi R \) (b) \( \frac{p}{180} \ × \ \pi R^2 \) (c) \( \frac{p}{360} \ × \ 2\pi R \) (d) \( \frac{p}{720} \ × \ 2\pi R^2 \)

- NCERT solutions for class 10 maths chapter 1 Real Numbers
- NCERT solutions for class 10 maths chapter 2 Polynomials
- NCERT solutions for class 10 maths chapter 3 Pair of linear equations in two variables
- NCERT solutions for class 10 maths chapter 4 Quadratic Equations
- NCERT solutions for class 10 maths chapter 5 Arithmetic Progressions
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- NCERT solutions for class 10 science chapter 2 Acids, Bases and Salts
- NCERT solutions for class 10 science chapter 3 Metals and Non Metals
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