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Finding the Fourth Proportional to 515.20, 772.24 and 309.72

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Solution

The fourth proportional to 515.20, 772.24 and 309.72 is: 464.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.20 : 772.24 = 309.72 : x
  2. Step 2: Convert to fraction form
    515.20/772.24 = 309.72/x
  3. Step 3: Cross multiply
    515.20x = 772.24 × 309.72
  4. Step 4: Simplify right side
    515.20x = 239,178.17
  5. Step 5: Solve for x
    x = 239,178.17/515.20
  6. Step 6: Final answer
    x = 464.24

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.