Wedding Cake Maths Equation SURFACE AREA

Question

A wedding cake has three tiers as indicated in the diagram below. Each tier is 10 cm high. The layers have radii 22 cm, 17 cm and 12 cm respectively. Find the total surface area of the cake, correct to the nearest cm 2.

Answer 1

The surface area (where we have to put the icing) for the top of each tier is πr². The side of the cake is the height times the circumference of the top = h*2πr.

So the total surface area (I'm assuming we are not counting the bottom of each layer) is:

π22² + 10*π*44 + π17² + 10*π*34 + π12² + 10*π*24

484π + 440π + 289π + 340π + 144π + 240π = 1941π π=3.141 6098 cm² is the area.