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The height and curved surface of a right...

The height and curved surface of a right circular cone are 24 cm and `550 cm^(2)`. Find the volume of this cone.

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To find the volume of the right circular cone given its height and curved surface area, we can follow these steps: ### Step 1: Identify the given values - Height (h) = 24 cm - Curved Surface Area (CSA) = 550 cm² ### Step 2: Use the formula for the curved surface area of a cone The formula for the curved surface area (CSA) of a cone is given by: \[ \text{CSA} = \pi r l \] where \( r \) is the radius and \( l \) is the slant height. ### Step 3: Express the slant height in terms of radius The slant height \( l \) can be calculated using the Pythagorean theorem: \[ l = \sqrt{r^2 + h^2} \] Substituting the height: \[ l = \sqrt{r^2 + 24^2} = \sqrt{r^2 + 576} \] ### Step 4: Substitute the expression for \( l \) into the CSA formula Substituting \( l \) into the CSA formula: \[ 550 = \pi r \sqrt{r^2 + 576} \] Using \( \pi \approx \frac{22}{7} \): \[ 550 = \frac{22}{7} r \sqrt{r^2 + 576} \] ### Step 5: Rearranging the equation Multiply both sides by 7 to eliminate the fraction: \[ 3850 = 22 r \sqrt{r^2 + 576} \] Now, divide both sides by 22: \[ \frac{3850}{22} = r \sqrt{r^2 + 576} \] Calculating \( \frac{3850}{22} \): \[ 175 = r \sqrt{r^2 + 576} \] ### Step 6: Square both sides to eliminate the square root \[ 175^2 = r^2 (r^2 + 576) \] Calculating \( 175^2 \): \[ 30625 = r^4 + 576r^2 \] ### Step 7: Rearranging the equation Rearranging gives us: \[ r^4 + 576r^2 - 30625 = 0 \] ### Step 8: Let \( x = r^2 \) and solve the quadratic equation This can be rewritten as: \[ x^2 + 576x - 30625 = 0 \] Using the quadratic formula \( x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \): - Here, \( a = 1 \), \( b = 576 \), and \( c = -30625 \). Calculating the discriminant: \[ b^2 - 4ac = 576^2 + 4 \cdot 30625 \] Calculating \( 576^2 = 331776 \) and \( 4 \cdot 30625 = 122500 \): \[ b^2 - 4ac = 331776 + 122500 = 454276 \] Now, calculating \( \sqrt{454276} \approx 674.5 \). ### Step 9: Finding the roots Now we can find \( x \): \[ x = \frac{-576 \pm 674.5}{2} \] Calculating the two possible values: 1. \( x = \frac{98.5}{2} = 49.25 \) (not valid as radius) 2. \( x = \frac{-1250.5}{2} = -625.25 \) (not valid) Thus, we can find \( r^2 = 49 \) which gives \( r = 7 \) cm. ### Step 10: Calculate the volume of the cone The volume \( V \) of the cone is given by: \[ V = \frac{1}{3} \pi r^2 h \] Substituting the values: \[ V = \frac{1}{3} \times \frac{22}{7} \times 7^2 \times 24 \] Calculating: \[ V = \frac{1}{3} \times \frac{22}{7} \times 49 \times 24 \] \[ = \frac{1}{3} \times 22 \times 7 \times 24 \] \[ = \frac{1}{3} \times 3696 = 1232 \text{ cm}^3 \] ### Final Answer The volume of the cone is \( 1232 \text{ cm}^3 \). ---
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NAGEEN PRAKASHAN ENGLISH-SURFACE AREA AND VOLUME-Exercise 13c
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  4. The cloth used in a conical tent is 330 square metre. Find its vertica...

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  5. The height and curved surface of a right circular cone are 24 cm and 5...

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  6. The base radius and total surface area of a cone are 7 cm and 704 cm^(...

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  7. The circumference of the base of a conical tent is 44 m and its height...

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  8. Find the volume of that largest cone that can be cut from a cube of ed...

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  9. Find the volume of that largest cone that can be cut from a cube of ed...

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  10. The base area and volume of a conical tent are 154 m^(2) and 1232 m^(3...

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  11. The volume of a cone is 18 pi cm^(3). Find its height if height and di...

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  12. Five person can accommodate in a conical tent. If each person requires...

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  13. The ratio of the base radius and height of a cone is 5 : 12. Find its ...

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  14. The ratio of the base radius and height of a cone is 5 : 12. Its volum...

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  15. The ratio of the base radius and height of a cone is 3 : 4. Its volume...

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  16. Find the total surface area of a right circular cone whose slant heigh...

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  17. The base and height of a cylinder and cone are same. The ratio of thei...

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  18. The sides containing right angle of a right angled triangle are 8 cm a...

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  19. The sides containing right angles of a right angled triangle are 8 cm ...

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  20. The sides containing right angles of a right angled triangle are 8 cm ...

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