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Finding the Fourth Proportional to 447.11, 670.71 and 138.90

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Solution

The fourth proportional to 447.11, 670.71 and 138.90 is: 208.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    447.11 : 670.71 = 138.90 : x
  2. Step 2: Convert to fraction form
    447.11/670.71 = 138.90/x
  3. Step 3: Cross multiply
    447.11x = 670.71 × 138.90
  4. Step 4: Simplify right side
    447.11x = 93,161.62
  5. Step 5: Solve for x
    x = 93,161.62/447.11
  6. Step 6: Final answer
    x = 208.36

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.