Answer:
The answer is $19.44
Explanation:
First, set up a proportion for tax and tip.
Your proportion should be x (the variable) over 28.80, equal to 25 over 100.
Then, cross multiply to set up an equation.
Your equation should be 100x is equal to 720.
Solve the equation by dividing both sides by 100, getting the amount for your variable, x, which should be $7.20.
Next, subtract $7.20 from the original price of 28.80, getting $21.60.
Next, set up the same proportion, except make it so that x is over $21.60 and 10 is over 100.
Cross multiply and set up your equation which is 100x is equal to 216.
Solve the equation by dividing both sides by 100, getting the value if x as $2.16.
Finally, subtract $2.16 from the sale price of $21.60, giving you your answer of $19.44.