A dishonest shopkeeper makes a cheating of 20% at the time of buying the goods and 40% cheating at the time of selling the goods. He promises to sell his goods at 20% loss. Find the profit percent.

60%

Let the actual weight = 1000 gm and CP = 1000Rs.

Weight for shopkeeper on buying (20% cheating)= 1000 × \(\frac{120}{100}\) = 1200 gm

Weight for shopkeeper on selling (40% cheating)= 1200 × \(\frac{100}{60}\) = 2000 gm

Weight for shopkeeper on selling (20% loss) = 2000 × \(\frac{80}{100}\) = 1600gm

So, CP = 1000, SP = 1600 ⇒ Profit = 600

Profit percent = \(\frac{600}{1000}\) × 100 = 60%