A grocer stacked oranges in a pile. The bottom layer was rectangular with 3 rows of 5 oranges each. In the second layer

[VJesus12]

A grocer stacked oranges in a pile. The bottom layer was rectangular with 3 rows of 5 oranges each. In the second layer from the bottom, each orange rested on 4 oranges from the bottom layer, and in the third layer, each orange rested on 4 oranges from the second layer. Which of the following is the maximum number of oranges that could have been in the third layer?

(A) 5
(B) 4
(C) 3
(D) 2
(E) 1

Answer: C

Source: GMAT Prep

[gmatbyexample]

A grocer stacked oranges in a pile. The bottom layer was rectangular with 3 rows of 5 oranges each. In the second layer from the bottom, each orange rested on 4 oranges from the bottom layer, and in the third layer, each orange rested on 4 oranges from the second layer. Which of the following is the maximum number of oranges that could have been in the third layer?

(A) 5
(B) 4
(C) 3
(D) 2
(E) 1

Answer: C

Source: GMAT Prep

So the second layer is a 2*4 matrix. There are three such possibilities in the third layer where the orange in the top layer will touch 4 oranges in the second layer.

[swerve]

A grocer stacked oranges in a pile. The bottom layer was rectangular with 3 rows of 5 oranges each. In the second layer from the bottom, each orange rested on 4 oranges from the bottom layer, and in the third layer, each orange rested on 4 oranges from the second layer. Which of the following is the maximum number of oranges that could have been in the third layer?

(A) 5
(B) 4
(C) 3
(D) 2
(E) 1

Answer: C

Source: GMAT Prep

Bottom Layer \(= 5 \times 3 = 15\)
2nd Layer \(= (5-1) \times (3-1) = 8\)
3rd Layer \(= (4-1) \times (2-1) = 3\)

Therefore, C