A trader sold an article at profit of 20%. Had he bought that article at 60% less price and sold it at Rs 90 less, then he would have gained 50%. What is the value (in Rs) of cost price?

Let cost price of article = Rs. $$100x$$

Profit % = 20%

=> Selling price = $$100x+(\frac{20}{100}\times100x)=Rs.$$ $$120x$$

If article is bought at 60% less price, => Cost price = $$\frac{(100-60)}{100}\times100x=Rs.$$ $$40x$$

Thus, selling price after 50% profit = $$\frac{150}{100}\times40x=Rs.$$ $$60x$$

According to ques, => $$60x=120x-90$$

=> $$120x-60x=60x=90$$

=> $$x=\frac{90}{60}=1.5$$

$$\therefore$$ Cost price = $$100\times1.5=Rs.$$ $$150$$

=> Ans - (A)