This question's explanation and your answers so far.
A社の子会社であるB社では，A社の製品も販売している。A社とB社の当期の売上高，売上原価，売上総利益が表のとおりであり，当期のA社の売上高におけるB社への販売分が2,000百万円である。このとき，連結損益計算書における当期仕入高は何百万円か。ここで，A社はB社からの仕入はないものとする。 A社損益計算書 単位 百万円
| 項目 | 金額 |
|---|---|
| 売上高 | 20,000 |
| 売上原価 | 12,000 |
| 期首棚卸高 | 1,000 |
| 当期仕入高 | 13,000 |
| 期末棚卸高 | 2,000 |
| 売上総利益 | 8,000 |
B社損益計算書 単位 百万円
| 項目 | 金額 |
|---|---|
| 売上高 | 6,000 |
| 売上原価 | 3,000 |
| 期首棚卸高 | 1,000 |
| 当期仕入高 | 3,000 |
| 期末棚卸高 | 1,000 |
| 売上総利益 | 3,000 |
11,000 is the value obtained by mistakenly subtracting the intra-group transaction of 2,000 from Company A's purchases of 13,000 (13,000 − 2,000). What should be eliminated is Company B's intra-group purchase on the buying side; subtracting it from Company A's purchases is the wrong target. Correctly, you eliminate the 2,000 only once after summing.
12,000 is the value obtained by eliminating the intra-group transaction of 2,000 twice from the simple total of 16,000 (16,000 − 2,000 − 2,000), or the error of simply picking Company A's cost of sales of 12,000. The intra-group purchase to be eliminated is only 2,000, and only once.
正解 The current-period purchases in the consolidated income statement are obtained by first summing both companies' current-period purchases and then eliminating the intra-group purchases. Simply adding Company A's current-period purchases of 13,000 and Company B's of 3,000 gives 16,000 million yen. Here, the 2,000 million yen that Company A sold to Company B is, from Company B's point of view, a purchase from Company A (an intra-group transaction), so it is already included in Company B's purchases of 3,000 and this 2,000 must be eliminated. Since the premise is that Company A makes no purchases from Company B, the only amount to eliminate is the 2,000 on Company B's side. Therefore 13,000 + 3,000 − 2,000 = 14,000 million yen, and the correct answer is ウ.
16,000 is merely the simple total of Company A's 13,000 and Company B's 3,000. It forgets to eliminate the 2,000 that Company B purchased from Company A, which is an intra-group transaction — the most common mistake in consolidated accounting.