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Finding the Fourth Proportional to 638.28, 880.62 and 389.52

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Solution

The fourth proportional to 638.28, 880.62 and 389.52 is: 537.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.28 : 880.62 = 389.52 : x
  2. Step 2: Convert to fraction form
    638.28/880.62 = 389.52/x
  3. Step 3: Cross multiply
    638.28x = 880.62 × 389.52
  4. Step 4: Simplify right side
    638.28x = 343,019.10
  5. Step 5: Solve for x
    x = 343,019.10/638.28
  6. Step 6: Final answer
    x = 537.41

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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.