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Finding the Fourth Proportional to 139.05, 208.31 and 119.68

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Solution

The fourth proportional to 139.05, 208.31 and 119.68 is: 179.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.05 : 208.31 = 119.68 : x
  2. Step 2: Convert to fraction form
    139.05/208.31 = 119.68/x
  3. Step 3: Cross multiply
    139.05x = 208.31 × 119.68
  4. Step 4: Simplify right side
    139.05x = 24,929.42
  5. Step 5: Solve for x
    x = 24,929.42/139.05
  6. Step 6: Final answer
    x = 179.28

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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.