What inequality would represents all possible values for x when x + 15 ≤ 40 ?

Jada has a meal in a restaurant she adds up the prices listed on the menu for everything they ordered and gets a subtotal of $42.00. when the check comes, it says they also need to pay $3.99 in sales tax. what percentage of the subtotal is the sales tax

The amount spent on food and drink by 20 customers is shown below what is the modal amount spent ?

Pls yall i really need the answer fr fr