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Finding the Fourth Proportional to 138.10, 206.94 and 125.20

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Solution

The fourth proportional to 138.10, 206.94 and 125.20 is: 187.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.10 : 206.94 = 125.20 : x
  2. Step 2: Convert to fraction form
    138.10/206.94 = 125.20/x
  3. Step 3: Cross multiply
    138.10x = 206.94 × 125.20
  4. Step 4: Simplify right side
    138.10x = 25,908.89
  5. Step 5: Solve for x
    x = 25,908.89/138.10
  6. Step 6: Final answer
    x = 187.61

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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.