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Finding the Fourth Proportional to 447.56, 671.34 and 139.40

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Solution

The fourth proportional to 447.56, 671.34 and 139.40 is: 209.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    447.56 : 671.34 = 139.40 : x
  2. Step 2: Convert to fraction form
    447.56/671.34 = 139.40/x
  3. Step 3: Cross multiply
    447.56x = 671.34 × 139.40
  4. Step 4: Simplify right side
    447.56x = 93,584.80
  5. Step 5: Solve for x
    x = 93,584.80/447.56
  6. Step 6: Final answer
    x = 209.10

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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.