Oh fun! You're doing percents!
Percents are quite easy when you know how to use them.
Ok, best way to calculate percents is to write a sentence.
113.4 is 27 percent of what?
these words translate into math symbols.
113.4=27%*x
27% then becomes a decimal
113.4=0.27*x
divide both sides by .27
113.4=0.27*x
0.27 0.27
420=x
so the regular price is $420