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Finding the Fourth Proportional to 619.32, 928.31 and 388.38

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Solution

The fourth proportional to 619.32, 928.31 and 388.38 is: 582.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.32 : 928.31 = 388.38 : x
  2. Step 2: Convert to fraction form
    619.32/928.31 = 388.38/x
  3. Step 3: Cross multiply
    619.32x = 928.31 × 388.38
  4. Step 4: Simplify right side
    619.32x = 360,535.10
  5. Step 5: Solve for x
    x = 360,535.10/619.32
  6. Step 6: Final answer
    x = 582.15

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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.