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Finding the Fourth Proportional to 638.13, 880.49 and 389.39

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Solution

The fourth proportional to 638.13, 880.49 and 389.39 is: 537.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.13 : 880.49 = 389.39 : x
  2. Step 2: Convert to fraction form
    638.13/880.49 = 389.39/x
  3. Step 3: Cross multiply
    638.13x = 880.49 × 389.39
  4. Step 4: Simplify right side
    638.13x = 342,857.18
  5. Step 5: Solve for x
    x = 342,857.18/638.13
  6. Step 6: Final answer
    x = 537.28

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.