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Finding the Fourth Proportional to 490.03, 676.21 and 280.21

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Solution

The fourth proportional to 490.03, 676.21 and 280.21 is: 386.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.03 : 676.21 = 280.21 : x
  2. Step 2: Convert to fraction form
    490.03/676.21 = 280.21/x
  3. Step 3: Cross multiply
    490.03x = 676.21 × 280.21
  4. Step 4: Simplify right side
    490.03x = 189,479.40
  5. Step 5: Solve for x
    x = 189,479.40/490.03
  6. Step 6: Final answer
    x = 386.67

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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.