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Finding the Fourth Proportional to 447.05, 670.34 and 138.85

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Solution

The fourth proportional to 447.05, 670.34 and 138.85 is: 208.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    447.05 : 670.34 = 138.85 : x
  2. Step 2: Convert to fraction form
    447.05/670.34 = 138.85/x
  3. Step 3: Cross multiply
    447.05x = 670.34 × 138.85
  4. Step 4: Simplify right side
    447.05x = 93,075.38
  5. Step 5: Solve for x
    x = 93,075.38/447.05
  6. Step 6: Final answer
    x = 208.20

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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.