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Finding the Fourth Proportional to 638.50, 881.38 and 417.64

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Solution

The fourth proportional to 638.50, 881.38 and 417.64 is: 576.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.50 : 881.38 = 417.64 : x
  2. Step 2: Convert to fraction form
    638.50/881.38 = 417.64/x
  3. Step 3: Cross multiply
    638.50x = 881.38 × 417.64
  4. Step 4: Simplify right side
    638.50x = 368,099.54
  5. Step 5: Solve for x
    x = 368,099.54/638.50
  6. Step 6: Final answer
    x = 576.51

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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.