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Finding the Fourth Proportional to 447.21, 670.57 and 138.98

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Solution

The fourth proportional to 447.21, 670.57 and 138.98 is: 208.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    447.21 : 670.57 = 138.98 : x
  2. Step 2: Convert to fraction form
    447.21/670.57 = 138.98/x
  3. Step 3: Cross multiply
    447.21x = 670.57 × 138.98
  4. Step 4: Simplify right side
    447.21x = 93,195.15
  5. Step 5: Solve for x
    x = 93,195.15/447.21
  6. Step 6: Final answer
    x = 208.39

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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.