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Finding the Fourth Proportional to 425.40, 638.26 and 219.84

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Solution

The fourth proportional to 425.40, 638.26 and 219.84 is: 329.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    425.40 : 638.26 = 219.84 : x
  2. Step 2: Convert to fraction form
    425.40/638.26 = 219.84/x
  3. Step 3: Cross multiply
    425.40x = 638.26 × 219.84
  4. Step 4: Simplify right side
    425.40x = 140,315.17
  5. Step 5: Solve for x
    x = 140,315.17/425.40
  6. Step 6: Final answer
    x = 329.84

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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.