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Finding the Fourth Proportional to 638.11, 880.54 and 402.06

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Solution

The fourth proportional to 638.11, 880.54 and 402.06 is: 554.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.11 : 880.54 = 402.06 : x
  2. Step 2: Convert to fraction form
    638.11/880.54 = 402.06/x
  3. Step 3: Cross multiply
    638.11x = 880.54 × 402.06
  4. Step 4: Simplify right side
    638.11x = 354,032.21
  5. Step 5: Solve for x
    x = 354,032.21/638.11
  6. Step 6: Final answer
    x = 554.81

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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.