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Finding the Fourth Proportional to 621.30, 929.55 and 405.30

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Solution

The fourth proportional to 621.30, 929.55 and 405.30 is: 606.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.30 : 929.55 = 405.30 : x
  2. Step 2: Convert to fraction form
    621.30/929.55 = 405.30/x
  3. Step 3: Cross multiply
    621.30x = 929.55 × 405.30
  4. Step 4: Simplify right side
    621.30x = 376,746.62
  5. Step 5: Solve for x
    x = 376,746.62/621.30
  6. Step 6: Final answer
    x = 606.38

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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.