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Finding the Fourth Proportional to 439.20, 658.80 and 266.40

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Solution

The fourth proportional to 439.20, 658.80 and 266.40 is: 399.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    439.20 : 658.80 = 266.40 : x
  2. Step 2: Convert to fraction form
    439.20/658.80 = 266.40/x
  3. Step 3: Cross multiply
    439.20x = 658.80 × 266.40
  4. Step 4: Simplify right side
    439.20x = 175,504.32
  5. Step 5: Solve for x
    x = 175,504.32/439.20
  6. Step 6: Final answer
    x = 399.60

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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.