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Finding the Fourth Proportional to 487.81, 673.19 and 280.81

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Solution

The fourth proportional to 487.81, 673.19 and 280.81 is: 387.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.81 : 673.19 = 280.81 : x
  2. Step 2: Convert to fraction form
    487.81/673.19 = 280.81/x
  3. Step 3: Cross multiply
    487.81x = 673.19 × 280.81
  4. Step 4: Simplify right side
    487.81x = 189,038.48
  5. Step 5: Solve for x
    x = 189,038.48/487.81
  6. Step 6: Final answer
    x = 387.52

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.