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Finding the Fourth Proportional to 138.32, 207.26 and 69.74

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Solution

The fourth proportional to 138.32, 207.26 and 69.74 is: 104.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.32 : 207.26 = 69.74 : x
  2. Step 2: Convert to fraction form
    138.32/207.26 = 69.74/x
  3. Step 3: Cross multiply
    138.32x = 207.26 × 69.74
  4. Step 4: Simplify right side
    138.32x = 14,452.93
  5. Step 5: Solve for x
    x = 14,452.93/138.32
  6. Step 6: Final answer
    x = 104.49

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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.