What does a ⊥ c the upside-down t mean? (this is from geometry)

The spring the owner of a sporting good store decreases the price of winter gloves from $10 to $8 each increases the price of swimming goggles from $8 to $10 without doing the math you think the percent decrease in the price of the gloves the same as the percent increase of the goggles explain why or why not

A50% increase followed by 33 1/2% decrease

Pls the last one and it has to be like number 6