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Finding the Fourth Proportional to 638.12, 880.40 and 401.96

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Solution

The fourth proportional to 638.12, 880.40 and 401.96 is: 554.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.12 : 880.40 = 401.96 : x
  2. Step 2: Convert to fraction form
    638.12/880.40 = 401.96/x
  3. Step 3: Cross multiply
    638.12x = 880.40 × 401.96
  4. Step 4: Simplify right side
    638.12x = 353,885.58
  5. Step 5: Solve for x
    x = 353,885.58/638.12
  6. Step 6: Final answer
    x = 554.58

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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.