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Finding the Fourth Proportional to 418.89, 628.30 and 213.42

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Solution

The fourth proportional to 418.89, 628.30 and 213.42 is: 320.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.89 : 628.30 = 213.42 : x
  2. Step 2: Convert to fraction form
    418.89/628.30 = 213.42/x
  3. Step 3: Cross multiply
    418.89x = 628.30 × 213.42
  4. Step 4: Simplify right side
    418.89x = 134,091.79
  5. Step 5: Solve for x
    x = 134,091.79/418.89
  6. Step 6: Final answer
    x = 320.11

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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.