Decrease £16855.21 by 3.5% give your answer rounded to 2 DP

You call the pizza store and find out that eachpizza has 12 slices. you expect 16 people tocome, and you estimate each person will eat 3slices. how many pizzas should you order

Anyone know? is appreciated! will mark brainliest if correct!

Gabriel determined that his total cost would be represented by 2.5x + 2y – 2. his sister states that the expression should be x + x + 0.5x + y + y – 2. who is correct? explain.