Question
a 40cm diameter birthday cake can feed 4 people.How many people will a 80 cm diameter cake feed?
Answers
Ms. Sue
A = pi * r^2
A = 3.14 * 20^2
A = 1256 sq. cm
1256 / 4 = 314 sq. cm per person
Do the same for the larger cake.
A = 3.14 * 20^2
A = 1256 sq. cm
1256 / 4 = 314 sq. cm per person
Do the same for the larger cake.
Tasmia
16 people
Tasmia
I forgot the explanation. 40cm is the diameter but th radius is 20. This means the area of the 40cm cake is actually 400pi. The 80cm cake will then be 1600pi. You get it from there.