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Finding the Fourth Proportional to 138.85, 207.19 and 137.63

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Solution

The fourth proportional to 138.85, 207.19 and 137.63 is: 205.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.85 : 207.19 = 137.63 : x
  2. Step 2: Convert to fraction form
    138.85/207.19 = 137.63/x
  3. Step 3: Cross multiply
    138.85x = 207.19 × 137.63
  4. Step 4: Simplify right side
    138.85x = 28,516.25
  5. Step 5: Solve for x
    x = 28,516.25/138.85
  6. Step 6: Final answer
    x = 205.38

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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.