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Finding the Fourth Proportional to 638.75, 881.89 and 403.02

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Solution

The fourth proportional to 638.75, 881.89 and 403.02 is: 556.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.75 : 881.89 = 403.02 : x
  2. Step 2: Convert to fraction form
    638.75/881.89 = 403.02/x
  3. Step 3: Cross multiply
    638.75x = 881.89 × 403.02
  4. Step 4: Simplify right side
    638.75x = 355,418.30
  5. Step 5: Solve for x
    x = 355,418.30/638.75
  6. Step 6: Final answer
    x = 556.43

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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.