Answer :

22.90*1.05=24.045
sales tax is 5% added to 100% of the original cost making the actaul cost including tax $24.045 
convert 5% to decimal = .05 multiply 22.90 x .05= 1.145 sales tax is $1.15 $22.90 = $1.15= $ 24.05 hat will cost $ 24.05 hope this helps