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Finding the Fourth Proportional to 425.66, 638.23 and 220.42

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Solution

The fourth proportional to 425.66, 638.23 and 220.42 is: 330.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    425.66 : 638.23 = 220.42 : x
  2. Step 2: Convert to fraction form
    425.66/638.23 = 220.42/x
  3. Step 3: Cross multiply
    425.66x = 638.23 × 220.42
  4. Step 4: Simplify right side
    425.66x = 140,679.32
  5. Step 5: Solve for x
    x = 140,679.32/425.66
  6. Step 6: Final answer
    x = 330.50

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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.