Matt H. answered 03/29/15
Tutor
5.0
(335)
At your kid's age, I hated math, too. Not any more!
Hi Cammy--
Try a few examples.
If the original price was 100, 40% off would be 40 dollars off for a price of 60 dollars.
To get back to 100, you'd have to add 40 dollars back on. 40 dollars is 2/3 of 60, or 66.6666 etc. percent.
Suppose the original cost is 20 dollars. 40% off, the cost would be 12 $. Adding the $8 dollars back on to the 12 means adding 2/3 of 12 onto it. (2/3--or 66.66666 etc. percent of 12 is 8, plus the 12 = 20.)
Try a few more and see if the pattern always holds true. :-)
Cheers,
Matt in New York