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Finding the Fourth Proportional to 638.83, 882.15 and 403.20

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Solution

The fourth proportional to 638.83, 882.15 and 403.20 is: 556.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.83 : 882.15 = 403.20 : x
  2. Step 2: Convert to fraction form
    638.83/882.15 = 403.20/x
  3. Step 3: Cross multiply
    638.83x = 882.15 × 403.20
  4. Step 4: Simplify right side
    638.83x = 355,682.88
  5. Step 5: Solve for x
    x = 355,682.88/638.83
  6. Step 6: Final answer
    x = 556.77

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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.