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Finding the Fourth Proportional to 638.08, 880.19 and 389.31

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Solution

The fourth proportional to 638.08, 880.19 and 389.31 is: 537.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.08 : 880.19 = 389.31 : x
  2. Step 2: Convert to fraction form
    638.08/880.19 = 389.31/x
  3. Step 3: Cross multiply
    638.08x = 880.19 × 389.31
  4. Step 4: Simplify right side
    638.08x = 342,664.08
  5. Step 5: Solve for x
    x = 342,664.08/638.08
  6. Step 6: Final answer
    x = 537.03

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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.