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Finding the Fourth Proportional to 139.41, 189.90 and 136.71

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Solution

The fourth proportional to 139.41, 189.90 and 136.71 is: 186.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.41 : 189.90 = 136.71 : x
  2. Step 2: Convert to fraction form
    139.41/189.90 = 136.71/x
  3. Step 3: Cross multiply
    139.41x = 189.90 × 136.71
  4. Step 4: Simplify right side
    139.41x = 25,961.23
  5. Step 5: Solve for x
    x = 25,961.23/139.41
  6. Step 6: Final answer
    x = 186.22

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Why These Related Problems?

These problems maintain the same ratio (1.36) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.