total surface area of a cone is 616 sq. cm.If the slant height of the cone is three times the radius of its base.Find its slant height.
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hiii!!!
here's ur answer...
length = slant height
ATQ,
the slant height of the cone is three times the radius of it's base.
let the radius be x.
therefore slant height is 3x.
TSA ( total surface area ) of the cone = 616cm²
therefore πrl + πr² = 616cm²
==> 22/7 × x × 3x + 22/7 × x × x = 616cm²
==> 22/7 × 3x² + 22/7 × x² = 616cm²
==> 66x²/7 + 22x²/7 = 616cm²
==> 88x²/7 = 616cm²
==> 88x² = 616/7
==> 88x² = 88
==> x² = 88/88
==> x² = 1
==> x = √1
==> x = 1cm
hence, radius of the cone is 1cm and slant height is = 3x = 3 × 1 = 3cm
hope it's right...
:D
here's ur answer...
length = slant height
ATQ,
the slant height of the cone is three times the radius of it's base.
let the radius be x.
therefore slant height is 3x.
TSA ( total surface area ) of the cone = 616cm²
therefore πrl + πr² = 616cm²
==> 22/7 × x × 3x + 22/7 × x × x = 616cm²
==> 22/7 × 3x² + 22/7 × x² = 616cm²
==> 66x²/7 + 22x²/7 = 616cm²
==> 88x²/7 = 616cm²
==> 88x² = 616/7
==> 88x² = 88
==> x² = 88/88
==> x² = 1
==> x = √1
==> x = 1cm
hence, radius of the cone is 1cm and slant height is = 3x = 3 × 1 = 3cm
hope it's right...
:D
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