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Finding the Fourth Proportional to 519.60, 728.40 and 519.60

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Solution

The fourth proportional to 519.60, 728.40 and 519.60 is: 728.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    519.60 : 728.40 = 519.60 : x
  2. Step 2: Convert to fraction form
    519.60/728.40 = 519.60/x
  3. Step 3: Cross multiply
    519.60x = 728.40 × 519.60
  4. Step 4: Simplify right side
    519.60x = 378,476.64
  5. Step 5: Solve for x
    x = 378,476.64/519.60
  6. Step 6: Final answer
    x = 728.40

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Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.