A moneybox contains only 50c and 20c coins. If there are 74 coins altogether, totalling $22.90, how many of each type of coins we're there?

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

Answer! if you don’t mind, can you explain

If a flying disk is 139 meters in the air and travels at an average of 13 m/s how long is it in the air