Solving Proportions

“A clothing store is having a sale: Buy 3 shirts and get the 4th for half price. If the regular price of a shirt is $18.50, define a variable and set up a proportion to determine the average cost per shirt if you buy 4 shirts. Do not solve. A baker needs to adjust a recipe. The original recipe uses 2.25 cups of sugar for every 2.75 cups of flour. If the baker wants to use 5.5 cups of flour, define a variable and set up a proportion to find out how much sugar is needed. Do not solve. A high-speed train travels 340 miles in 2.5 hours. Assuming a constant speed, define a variable and set up a proportion to determine how long it will take to travel 816 miles. Do not solve.”