Given:
A store has clearance items that have been marked down by 40%.
Let the original price = x
So, the price after markdown by 40% will be 60% of the original price
So, the price will be 60% of x = 0.6x
They are having a sale, advertising an additional 50% off clearance items.
So, the price will be 50% of 0.6x
So, the price will be as follows:

So, the answer will be:
The percentage of the original price do you end up paying = 30%