If an article is sold at 19% profit instead of 12% profit, then the profit would be Rs. 105 more. What is the cost price?

1500 Rs.

Let the cost price of an article be Rs. x.
(19% of x) - (12% of x) = 105
19x/100 - 12x/100 = 105 => 7x = 105 * 100
=> x = 1500
Cost price = Rs. 1500