Question

Tiffany buys a basket of watermelons on sale for $9 b4 the sales tax ,The sales tax is 9%

Answer 1

It would be: 9 + (9 * 9%)
= 9 + (9 * 0.09)   [ 9% = 0.09 ]
= 9 + 0.81
= 9.81

In short, Your Answer would be $9.81

Hope this helps!