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Finding the Fourth Proportional to 638.90, 881.42 and 417.47

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Solution

The fourth proportional to 638.90, 881.42 and 417.47 is: 575.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.90 : 881.42 = 417.47 : x
  2. Step 2: Convert to fraction form
    638.90/881.42 = 417.47/x
  3. Step 3: Cross multiply
    638.90x = 881.42 × 417.47
  4. Step 4: Simplify right side
    638.90x = 367,964.87
  5. Step 5: Solve for x
    x = 367,964.87/638.90
  6. Step 6: Final answer
    x = 575.93

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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.