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Finding the Fourth Proportional to 354.20, 488.70 and 206.80

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Solution

The fourth proportional to 354.20, 488.70 and 206.80 is: 285.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    354.20 : 488.70 = 206.80 : x
  2. Step 2: Convert to fraction form
    354.20/488.70 = 206.80/x
  3. Step 3: Cross multiply
    354.20x = 488.70 × 206.80
  4. Step 4: Simplify right side
    354.20x = 101,061.94
  5. Step 5: Solve for x
    x = 101,061.94/354.20
  6. Step 6: Final answer
    x = 285.33

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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.