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Finding the Fourth Proportional to 485.87, 730.31 and 280.85

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Solution

The fourth proportional to 485.87, 730.31 and 280.85 is: 422.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.87 : 730.31 = 280.85 : x
  2. Step 2: Convert to fraction form
    485.87/730.31 = 280.85/x
  3. Step 3: Cross multiply
    485.87x = 730.31 × 280.85
  4. Step 4: Simplify right side
    485.87x = 205,102.51
  5. Step 5: Solve for x
    x = 205,102.51/485.87
  6. Step 6: Final answer
    x = 422.14

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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.