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Finding the Fourth Proportional to 511.68, 768.78 and 425.64

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Solution

The fourth proportional to 511.68, 768.78 and 425.64 is: 639.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.68 : 768.78 = 425.64 : x
  2. Step 2: Convert to fraction form
    511.68/768.78 = 425.64/x
  3. Step 3: Cross multiply
    511.68x = 768.78 × 425.64
  4. Step 4: Simplify right side
    511.68x = 327,223.52
  5. Step 5: Solve for x
    x = 327,223.52/511.68
  6. Step 6: Final answer
    x = 639.51

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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.