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Finding the Fourth Proportional to 317.20, 440.26 and 309.28

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Solution

The fourth proportional to 317.20, 440.26 and 309.28 is: 429.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    317.20 : 440.26 = 309.28 : x
  2. Step 2: Convert to fraction form
    317.20/440.26 = 309.28/x
  3. Step 3: Cross multiply
    317.20x = 440.26 × 309.28
  4. Step 4: Simplify right side
    317.20x = 136,163.61
  5. Step 5: Solve for x
    x = 136,163.61/317.20
  6. Step 6: Final answer
    x = 429.27

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.