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Finding the Fourth Proportional to 672.78, 928.02 and 439.90

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Solution

The fourth proportional to 672.78, 928.02 and 439.90 is: 606.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    672.78 : 928.02 = 439.90 : x
  2. Step 2: Convert to fraction form
    672.78/928.02 = 439.90/x
  3. Step 3: Cross multiply
    672.78x = 928.02 × 439.90
  4. Step 4: Simplify right side
    672.78x = 408,236.00
  5. Step 5: Solve for x
    x = 408,236.00/672.78
  6. Step 6: Final answer
    x = 606.79

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.