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Finding the Fourth Proportional to 511.34, 765.79 and 408.70

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Solution

The fourth proportional to 511.34, 765.79 and 408.70 is: 612.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.34 : 765.79 = 408.70 : x
  2. Step 2: Convert to fraction form
    511.34/765.79 = 408.70/x
  3. Step 3: Cross multiply
    511.34x = 765.79 × 408.70
  4. Step 4: Simplify right side
    511.34x = 312,978.31
  5. Step 5: Solve for x
    x = 312,978.31/511.34
  6. Step 6: Final answer
    x = 612.08

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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.