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Finding the Fourth Proportional to 138.38, 206.57 and 123.13

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Solution

The fourth proportional to 138.38, 206.57 and 123.13 is: 183.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.38 : 206.57 = 123.13 : x
  2. Step 2: Convert to fraction form
    138.38/206.57 = 123.13/x
  3. Step 3: Cross multiply
    138.38x = 206.57 × 123.13
  4. Step 4: Simplify right side
    138.38x = 25,433.83
  5. Step 5: Solve for x
    x = 25,433.83/138.38
  6. Step 6: Final answer
    x = 183.79

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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.