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Finding the Fourth Proportional to 138.00, 206.74 and 69.35

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Solution

The fourth proportional to 138.00, 206.74 and 69.35 is: 103.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.00 : 206.74 = 69.35 : x
  2. Step 2: Convert to fraction form
    138.00/206.74 = 69.35/x
  3. Step 3: Cross multiply
    138.00x = 206.74 × 69.35
  4. Step 4: Simplify right side
    138.00x = 14,338.37
  5. Step 5: Solve for x
    x = 14,338.37/138.00
  6. Step 6: Final answer
    x = 103.90

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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.