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Finding the Fourth Proportional to 138.86, 207.19 and 130.60

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Solution

The fourth proportional to 138.86, 207.19 and 130.60 is: 194.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.86 : 207.19 = 130.60 : x
  2. Step 2: Convert to fraction form
    138.86/207.19 = 130.60/x
  3. Step 3: Cross multiply
    138.86x = 207.19 × 130.60
  4. Step 4: Simplify right side
    138.86x = 27,059.01
  5. Step 5: Solve for x
    x = 27,059.01/138.86
  6. Step 6: Final answer
    x = 194.87

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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.