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Finding the Fourth Proportional to 439.70, 658.66 and 208.81

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Solution

The fourth proportional to 439.70, 658.66 and 208.81 is: 312.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    439.70 : 658.66 = 208.81 : x
  2. Step 2: Convert to fraction form
    439.70/658.66 = 208.81/x
  3. Step 3: Cross multiply
    439.70x = 658.66 × 208.81
  4. Step 4: Simplify right side
    439.70x = 137,533.03
  5. Step 5: Solve for x
    x = 137,533.03/439.70
  6. Step 6: Final answer
    x = 312.79

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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.