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Finding the Fourth Proportional to 511.20, 763.79 and 393.39

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Solution

The fourth proportional to 511.20, 763.79 and 393.39 is: 587.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.20 : 763.79 = 393.39 : x
  2. Step 2: Convert to fraction form
    511.20/763.79 = 393.39/x
  3. Step 3: Cross multiply
    511.20x = 763.79 × 393.39
  4. Step 4: Simplify right side
    511.20x = 300,465.38
  5. Step 5: Solve for x
    x = 300,465.38/511.20
  6. Step 6: Final answer
    x = 587.76

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.