Xenia is ordering a cake for her friend’s wedding. She knows that there will be 110 guests at the wedding, and she is trying to decide how large a cake to order. She has been told that each guest should get a piece of cake that is 4 inches by 4 inches. She would like to buy a tiered, square three-layer cake and is trying to decide which sizes of cakes to order. Which combination of cakes should she get? The available sizes, in inches, are:
32 × 32
28 × 28
24 × 24
20 × 20
16 × 16
12 × 12
8 × 8

Question

Xenia is ordering a cake for her friend’s wedding. She knows that there will be 110 guests at the wedding, and she is trying to decide how large a cake to order. She has been told that each guest should get a piece of cake that is 4 inches by 4 inches. She would like to buy a tiered, square three-layer cake and is trying to decide which sizes of cakes to order. Which combination of cakes should she get? The available sizes, in inches, are: 
32  ×  32
28  ×  28
24  ×  24
20  ×  20
16  ×  16
12  ×  12
8  ×  8

anonymous · Answer

Answers: 
A. 8  ×  8,  12  ×  12,  and 16  ×  16
B. 16  ×  16,  20  ×  20,  and 24  ×  24
C. 20  ×  20,  24  ×  24,  and 28  ×  28
D. 24  ×  24,  28  ×  28,  and 32  ×  32