The 10" pizza sells for \$ 3.99 at my favorite pizza store. The store claims they have a great deal on the large 14" pizza, which is specially priced at \$ 7.04. What is the per cent discount the store is offering?

Calculate area to price ratio: 10" pizza area = π×5² = 25π sq in, price = $3.99, so $3.99/25π = \$0.0508 per sq in. 14" pizza area = π×7² = 49π sq in. At same ratio: 49π×\$0.0508 = $7.82. Actual price $7.04 is \$0.78 less. Discount = 0.78/7.82 = 0.0997 ≈ 10%. Alternative method: area increases by factor 49/25 = 1.96. Price should increase to \$3.99×1.96 = \$7.82. Actual is \$7.04, so discount = (7.82-7.04)/7.82 ≈ 10%.