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Finding the Fourth Proportional to 640.31, 958.85 and 511.79

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Solution

The fourth proportional to 640.31, 958.85 and 511.79 is: 766.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.31 : 958.85 = 511.79 : x
  2. Step 2: Convert to fraction form
    640.31/958.85 = 511.79/x
  3. Step 3: Cross multiply
    640.31x = 958.85 × 511.79
  4. Step 4: Simplify right side
    640.31x = 490,727.28
  5. Step 5: Solve for x
    x = 490,727.28/640.31
  6. Step 6: Final answer
    x = 766.39

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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.