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Finding the Fourth Proportional to 638.28, 885.06 and 626.40

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Solution

The fourth proportional to 638.28, 885.06 and 626.40 is: 868.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.28 : 885.06 = 626.40 : x
  2. Step 2: Convert to fraction form
    638.28/885.06 = 626.40/x
  3. Step 3: Cross multiply
    638.28x = 885.06 × 626.40
  4. Step 4: Simplify right side
    638.28x = 554,401.58
  5. Step 5: Solve for x
    x = 554,401.58/638.28
  6. Step 6: Final answer
    x = 868.59

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.