Correct Answer - Option 1 : 42.85% Loss

**Given: **

40% of CP = 70% of SP

**Formula used: **

Profit = Selling Price – Cost Price

Profit % = (Profit)/(Cost price) × 100

Loss = Cost Price – Selling Price

Loss % = (Loss)/(Cost price) × 100

**Calculation: **

Let the CP be ‘a’

According to the question,

⇒ 40/100 × a = 70/100 × SP

⇒ SP = 40a/70

⇒ SP = 4a/7

Loss = CP – SP

⇒ Loss = a – 4a/7 = 3a/7

Loss % = Loss/CP × 100

⇒ Loss % = (3a/7)/a × 100

⇒ Loss % = 300/7 % = 42.85%

**∴**** The loss percent is 42.85%**

**Alternate Method: **

40% of CP = 70% of SP

⇒ 40/100 × CP = 70/100 × SP

⇒ SP/CP = 4/7

Loss = CP – SP

⇒ Loss = 7 – 4 = 3

⇒ Loss % = Loss/CP × 100

⇒ Loss % = 3/7 × 100 = 300/7 = 42.85%

**∴**** The loss percent is 42.85%**