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Finding the Fourth Proportional to 487.80, 673.07 and 280.76

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Solution

The fourth proportional to 487.80, 673.07 and 280.76 is: 387.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.80 : 673.07 = 280.76 : x
  2. Step 2: Convert to fraction form
    487.80/673.07 = 280.76/x
  3. Step 3: Cross multiply
    487.80x = 673.07 × 280.76
  4. Step 4: Simplify right side
    487.80x = 188,971.13
  5. Step 5: Solve for x
    x = 188,971.13/487.80
  6. Step 6: Final answer
    x = 387.39

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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.