Question

a store is having a 20% off sale if the reduced price of an item is $90.40 what was its original price

Answer 1

This is the price with a 20% off sale.
$90,40 = (100%-20%) = 80%

If you divide 80% with 5 it turns into 20%.
($90,40/4) = $22,60 = 20%

Then you multiply the 20% with 5 to get 100% = The original price.
($20,60*5) = $103 = 100%

You don’t have to use my tactic or the one the teacher says, use the one that works and is the most suitable for you!