Question

the radius and slant height of a cone are in the ratio 4:7find it's slant height if it's curved surface area is 3168m2​

Answer 1

Answer:

GIVEN:

THE RATIO AND SLANT HEIGHT OF THE CONE ARE IN THE RATIO 4:7 .

SURFACE AREA=3168 M^2

TO FIND:

SLANT HEIGHT.

FORMULA TO BE USED:

CURVED SURFACE AREA OF CONE:

$\pi \: rl$

WHERE,

R=RADIUS

L=SLANT HEIGHT.

SOLUTION:

LET THE RADIUS AND SLANT HEIGHT BE 4X AND 7X RESPECTIVELY.

TAKE PI=22/7.

$3168 = \frac{22}{7} \times 4x \times 7x \\ \\ = > \frac{3168 \times 7}{22} = 28 {x}^{2} \\ \\ = > 1008 = 28 {x}^{2} \\ \\ = > {x}^{2} = \frac{1008}{28} = 36 \\ \\ = > x = \sqrt{36} = 6$

WE GOT X=6

RADIUS =4X=4×6=24 M

SLANT HEIGHT =7X=7×6=42M

HENCE THE LENGTH OF THE SLANT HEIGHT IS 42 M.