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Finding the Fourth Proportional to 547.20, 820.90 and 209.09

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Solution

The fourth proportional to 547.20, 820.90 and 209.09 is: 313.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    547.20 : 820.90 = 209.09 : x
  2. Step 2: Convert to fraction form
    547.20/820.90 = 209.09/x
  3. Step 3: Cross multiply
    547.20x = 820.90 × 209.09
  4. Step 4: Simplify right side
    547.20x = 171,640.43
  5. Step 5: Solve for x
    x = 171,640.43/547.20
  6. Step 6: Final answer
    x = 313.67

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.