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Finding the Fourth Proportional to 511.00, 764.78 and 388.55

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Solution

The fourth proportional to 511.00, 764.78 and 388.55 is: 581.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.00 : 764.78 = 388.55 : x
  2. Step 2: Convert to fraction form
    511.00/764.78 = 388.55/x
  3. Step 3: Cross multiply
    511.00x = 764.78 × 388.55
  4. Step 4: Simplify right side
    511.00x = 297,155.24
  5. Step 5: Solve for x
    x = 297,155.24/511.00
  6. Step 6: Final answer
    x = 581.52

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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.