Respuesta :
Your answer is D.
The jeans are 40% off (because you add 20% more).
And the original cost of the jeans is $30.
You could have done:
30 · 0.40 = 12 (Find 40% of $30, then subtract 30 by 40% of 30 to get the new sale price]
30 - 12 = 18
1 - 0.40 = 0.60 (You subtract 1 by 0.40 to get 0.60, which is the % of the original price that you have to pay)
30 · 0.60 = 18