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Finding the Fourth Proportional to 638.58, 881.46 and 417.90

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Solution

The fourth proportional to 638.58, 881.46 and 417.90 is: 576.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.58 : 881.46 = 417.90 : x
  2. Step 2: Convert to fraction form
    638.58/881.46 = 417.90/x
  3. Step 3: Cross multiply
    638.58x = 881.46 × 417.90
  4. Step 4: Simplify right side
    638.58x = 368,362.13
  5. Step 5: Solve for x
    x = 368,362.13/638.58
  6. Step 6: Final answer
    x = 576.85

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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.