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Finding the Fourth Proportional to 402.20, 603.20 and 219.50

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Solution

The fourth proportional to 402.20, 603.20 and 219.50 is: 329.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    402.20 : 603.20 = 219.50 : x
  2. Step 2: Convert to fraction form
    402.20/603.20 = 219.50/x
  3. Step 3: Cross multiply
    402.20x = 603.20 × 219.50
  4. Step 4: Simplify right side
    402.20x = 132,402.40
  5. Step 5: Solve for x
    x = 132,402.40/402.20
  6. Step 6: Final answer
    x = 329.20

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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.