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Finding the Fourth Proportional to 490.19, 676.42 and 280.42

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Solution

The fourth proportional to 490.19, 676.42 and 280.42 is: 386.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.19 : 676.42 = 280.42 : x
  2. Step 2: Convert to fraction form
    490.19/676.42 = 280.42/x
  3. Step 3: Cross multiply
    490.19x = 676.42 × 280.42
  4. Step 4: Simplify right side
    490.19x = 189,681.70
  5. Step 5: Solve for x
    x = 189,681.70/490.19
  6. Step 6: Final answer
    x = 386.96

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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.