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Finding the Fourth Proportional to 487.38, 672.57 and 280.38

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Solution

The fourth proportional to 487.38, 672.57 and 280.38 is: 386.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.38 : 672.57 = 280.38 : x
  2. Step 2: Convert to fraction form
    487.38/672.57 = 280.38/x
  3. Step 3: Cross multiply
    487.38x = 672.57 × 280.38
  4. Step 4: Simplify right side
    487.38x = 188,575.18
  5. Step 5: Solve for x
    x = 188,575.18/487.38
  6. Step 6: Final answer
    x = 386.92

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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.