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Finding the Fourth Proportional to 638.50, 881.14 and 405.62

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Solution

The fourth proportional to 638.50, 881.14 and 405.62 is: 559.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.50 : 881.14 = 405.62 : x
  2. Step 2: Convert to fraction form
    638.50/881.14 = 405.62/x
  3. Step 3: Cross multiply
    638.50x = 881.14 × 405.62
  4. Step 4: Simplify right side
    638.50x = 357,408.01
  5. Step 5: Solve for x
    x = 357,408.01/638.50
  6. Step 6: Final answer
    x = 559.76

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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.