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Finding the Fourth Proportional to 425.97, 638.90 and 137.40

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Solution

The fourth proportional to 425.97, 638.90 and 137.40 is: 206.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    425.97 : 638.90 = 137.40 : x
  2. Step 2: Convert to fraction form
    425.97/638.90 = 137.40/x
  3. Step 3: Cross multiply
    425.97x = 638.90 × 137.40
  4. Step 4: Simplify right side
    425.97x = 87,784.17
  5. Step 5: Solve for x
    x = 87,784.17/425.97
  6. Step 6: Final answer
    x = 206.08

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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.