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Finding the Fourth Proportional to 207.05, 309.77 and 138.61

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Solution

The fourth proportional to 207.05, 309.77 and 138.61 is: 207.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    207.05 : 309.77 = 138.61 : x
  2. Step 2: Convert to fraction form
    207.05/309.77 = 138.61/x
  3. Step 3: Cross multiply
    207.05x = 309.77 × 138.61
  4. Step 4: Simplify right side
    207.05x = 42,934.98
  5. Step 5: Solve for x
    x = 42,934.98/207.05
  6. Step 6: Final answer
    x = 207.37

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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.