The lateral surface area and the area of the base of the cone are in the ratio 5:4. If the volume of the cone is 1024 pi m3, then find the height of the cone . Pls answer this early experts.
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Let r be the radius of base, l be the slant height and h be the height of cone.Now, LSA = πrlArea of base = πr2LSAArea of base = πrlπr2 = lr 54 = lr4l = 5rl = 5r4Now, volume of cone = 13πr2h1024π = 13πr2l2 - r21024 = r23 25r216 - r2 3072 = r29r2163072 = r2 × 3r43r3 = 12288r3 = 4096r = 16Now, l = 5r4 = 5 × 164 = 20 mNow, h = l2 - r2 = 202 - 162 = 400 - 256 = 144h = 12 m

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hmmm good question'
 
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good and well ques.
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