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Finding the Fourth Proportional to 426.78, 640.17 and 384.30

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Solution

The fourth proportional to 426.78, 640.17 and 384.30 is: 576.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.78 : 640.17 = 384.30 : x
  2. Step 2: Convert to fraction form
    426.78/640.17 = 384.30/x
  3. Step 3: Cross multiply
    426.78x = 640.17 × 384.30
  4. Step 4: Simplify right side
    426.78x = 246,017.33
  5. Step 5: Solve for x
    x = 246,017.33/426.78
  6. Step 6: Final answer
    x = 576.45

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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.