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Finding the Fourth Proportional to 459.05, 687.85 and 390.29

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Solution

The fourth proportional to 459.05, 687.85 and 390.29 is: 584.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    459.05 : 687.85 = 390.29 : x
  2. Step 2: Convert to fraction form
    459.05/687.85 = 390.29/x
  3. Step 3: Cross multiply
    459.05x = 687.85 × 390.29
  4. Step 4: Simplify right side
    459.05x = 268,456.56
  5. Step 5: Solve for x
    x = 268,456.56/459.05
  6. Step 6: Final answer
    x = 584.82

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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.