Question

FIND THE TOTAL SURFACE AREA OF A CONE, IF ITS SLANT HEIGHT IS 21 M AND DIAMETER OF ITS BASE IS 24 M
(Hint: the answer is not 124.57)​

Answer 1

TSA of cone is πr(l+r)

22/7×12×21×12

22×12×12×3

22×144×3

9504msq.

Answer 2

Answer:

Total Surface Area = 1244.57m²

Step-by-step explanation:

Slant height (l) = 21m

Diameter (d) = 24m

Radius (r) = d/2 = 24/2 = 12m

∴ Total Surface Area of a cone = $\pi$r(l+r)

                                                    = 22/7 x 12 (21 + 12)

                                                    = 22/7 x 12 x 33

                                                    = 22/7 x 396

                                                    = 8712/7

                                                    = 1244.57m²

∴ The Total Surface Area of the cone is 1244.57m².

Hope this helps :)