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Finding the Fourth Proportional to 479.78, 720.95 and 260.55

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Solution

The fourth proportional to 479.78, 720.95 and 260.55 is: 391.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.78 : 720.95 = 260.55 : x
  2. Step 2: Convert to fraction form
    479.78/720.95 = 260.55/x
  3. Step 3: Cross multiply
    479.78x = 720.95 × 260.55
  4. Step 4: Simplify right side
    479.78x = 187,843.52
  5. Step 5: Solve for x
    x = 187,843.52/479.78
  6. Step 6: Final answer
    x = 391.52

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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.