Correct Answer - Option 4 : Neither I nor II
Given:
CP of table = T
CP of chair = C
T = C + 400
Profit on table = 15%
Profit on chair = 22%
Total gain = Rs. 615
Formula Used:
Profit = SP – CP
Profit% = (Profit /CP) × 100
SP = {(100 + P%)/100} × CP
Where P → Profit, CP → cost price and SP → selling price.
Calculation:
Profit on table = (15/100) × T
Profit on chair = (22/100) × C
Overall gain = Rs. 615
⇒ Profit on table + Profit on chair = 615
⇒ (15/100) × T + (22/100) × C = 615
Putting T = C + 400
⇒ (15/100) × (C + 400) + (22/100) × C = 615
⇒ (37/100) × C + 60 = 615
⇒ (37/100) × C = 555
⇒ C = 555 × 100/37
⇒ C = 1500
T = 1500 + 400
⇒ T = 1900
I. Average cost price of both is Rs. 1600
(1500 + 1900)/2 = 3400/2
⇒ 1700
⇒ I is incorrect
II. Selling price of chair is Rs. 1800
SP of chair = (100 + 22)/100 × 1500
⇒ 122 × 15
⇒ 1830
⇒ II is incorrect
∴ Neither I nor II is correct.