A circular fountain has a diameter of 14 feet. What is its circumference? (Use π ≈ 22/7)

Circumference = π × diameter. Using π ≈ 22/7: C = (22/7) × 14 = 22 × 2 = 44 feet. Alternative: C = 2 × π × radius; radius = diameter/2 = 7; C = 2 × (22/7) × 7 = 2 × 22 = 44 feet. Both forms of the formula give the same answer. When diameter is a multiple of 7, using π = 22/7 makes the arithmetic clean. Use π ≈ 3.14 for other diameters. Don't confuse circumference (distance around) with area (space inside): area of this fountain = π × r² = (22/7) × 49 = 154 square feet. Many ASVAB problems test the difference. Real-world applications: edging needed (circumference), surface area for paint (area), water volume (volume formula involving radius squared). Memorize: C = π × d = 2π × r; A = π × r². The square in the area formula makes area grow much faster than circumference as radius increases.