Answer:
$24
Step-by-step explanation:
Since 25% is off the price of the shirt, she bought the shirt at 75% of it's cost price. This difference between the full cost and the 75% is what she saved (i.e. 25% was the savings)
So, if the shirt costs x dollars:
$6 = 25% of x
= ( 25/100)*X = 0.25X
X = $6/0.25 = $6x4
X = $24
