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Finding the Fourth Proportional to 138.60, 208.14 and 104.25

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Solution

The fourth proportional to 138.60, 208.14 and 104.25 is: 156.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.60 : 208.14 = 104.25 : x
  2. Step 2: Convert to fraction form
    138.60/208.14 = 104.25/x
  3. Step 3: Cross multiply
    138.60x = 208.14 × 104.25
  4. Step 4: Simplify right side
    138.60x = 21,698.60
  5. Step 5: Solve for x
    x = 21,698.60/138.60
  6. Step 6: Final answer
    x = 156.56

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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.