The weighted average unit cost takes into account both the cost and the quantity:
Weighted Average=∑(Unit Cost×Quantity)∑Quantities\text{Weighted Average} = \frac{\sum (\text{Unit Cost} \times \text{Quantity})}{\sum \text{Quantities}}Weighted Average=∑Quantities∑(Unit Cost×Quantity)​ Multiplying each unit cost by the respective quantity:
(55.00×147)+(34.50×143)+(37.30×462)+(55.00×530)+(40.00×308)+(26.78×45)+(46.59×256)+(75.00×176)+(65.00×80)(55.00 \times 147) + (34.50 \times 143) + (37.30 \times 462) + (55.00 \times 530) + (40.00 \times 308) + (26.78 \times 45) + (46.59 \times 256) + (75.00 \times 176) + (65.00 \times 80)(55.00×147)+(34.50×143)+(37.30×462)+(55.00×530)+(40.00×308)+(26.78×45)+(46.59×256)+(75.00×176)+(65.00×80) Summing these and dividing by the total quantity:
Weighted Average=20941.6+4933.5+17247.6+29150.0+12320.0+1205.1+11926.1+13200.0+5200.02147\text{Weighted Average} = \frac{20941.6 + 4933.5 + 17247.6 + 29150.0 + 12320.0 + 1205.1 + 11926.1 + 13200.0 + 5200.0}{2147}Weighted Average=214720941.6+4933.5+17247.6+29150.0+12320.0+1205.1+11926.1+13200.0+5200.0​ This gives a weighted average of approximately $47.63, making B. $47.63 the correct answer.