Ewan is building a maze for his pet rats out of 2x4s. He needs two pieces that are 2 ¾ feet long, one that is 3.5 feet long and two that are 1 5/8 feet long. Ewan can buy wood that is 84 inches long at $2.35 per board, 96 inches long that costs $3.60 for each board, or a 10 foot board, for $4.61.

2 pieces at 2 3/4 feet is 2 x 2 foot 9 inches = 5 foot 6 inches

1 piece that is 3.5 feet is 3 feet 6 inches

2 pieces that are 1 5/8 feet are 2 x 1 foot 7 1/2 inches = 3 feet 3 inches

I think there should be more to the question. If you are looking for the best combination to buy it would be two 7 foot boards