Q. 45.0( 1 Vote )

Answer :

Given: slant height of bucket = l = 45 cm

Radius of bottom circle = r = 7 cm

Radius of top circle = R = 28 cm

As the bucket is in the form of frustum

Formula: Total surface area of frustum = πr^{2} + πR^{2} + π(R + r)l cm^{2}

Now we have asked curved surface area, so we should subtract the top and bottom surface

areas which are flat circles.

Surface area of top = πr^{2}

Surface area of bottom = πR^{2}

∴ Curved surface area = total surface area – πr^{2} - πR^{2} cm^{2}

= πr^{2} + πR^{2} + π(R + r)l – πr^{2} - πR^{2} cm^{2}

= π(R + r)l cm^{2}

= 3.14 × (28 + 7) × 45 cm^{2}

= 3.14 × 35 × 45 cm^{2}

= 4945.5 cm^{2}

Therefore, curved surface area of bucket = 4945.5 cm^{2}

Rate this question :

How useful is this solution?

We strive to provide quality solutions. Please rate us to serve you better.

PREVIOUSA circus tent is cylindrical to a height of 4 m and conical above it. If its diameter is 105 m and its slant height is 40 m, find the total area of the canvas required.NEXTA solid metal cone with radius of base 12 cm and height 24 cm is melted to form solid spherical balls of diameter 6 cm each. Find the number of balls formed.