Christian purchased a brand new shirt for his birthday. the shirt was originally $50 but christian only paid $30. what was the percent of change (precent decrease proportion)

20 percent of ??? Not sure that's what I think?

Its 60% off because you have to try to multiply 50 by a a percentage. the lower the percentage the lower the cost is so the higher the kinda less money you have to pay. for example. 50x20%. 20% turns to .20 or .2. so lets say it costed 50 dollars and ended up paying 10 dollars. well you multiple 50 times a low percentage and see if you end up with 10 dollars