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Finding the Fourth Proportional to 139.32, 207.99 and 129.87

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Solution

The fourth proportional to 139.32, 207.99 and 129.87 is: 193.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.32 : 207.99 = 129.87 : x
  2. Step 2: Convert to fraction form
    139.32/207.99 = 129.87/x
  3. Step 3: Cross multiply
    139.32x = 207.99 × 129.87
  4. Step 4: Simplify right side
    139.32x = 27,011.66
  5. Step 5: Solve for x
    x = 27,011.66/139.32
  6. Step 6: Final answer
    x = 193.88

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.