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Finding the Fourth Proportional to 638.28, 881.16 and 405.84

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Solution

The fourth proportional to 638.28, 881.16 and 405.84 is: 560.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.28 : 881.16 = 405.84 : x
  2. Step 2: Convert to fraction form
    638.28/881.16 = 405.84/x
  3. Step 3: Cross multiply
    638.28x = 881.16 × 405.84
  4. Step 4: Simplify right side
    638.28x = 357,609.97
  5. Step 5: Solve for x
    x = 357,609.97/638.28
  6. Step 6: Final answer
    x = 560.27

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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.