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Finding the Fourth Proportional to 137.60, 206.14 and 86.30

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Solution

The fourth proportional to 137.60, 206.14 and 86.30 is: 129.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.60 : 206.14 = 86.30 : x
  2. Step 2: Convert to fraction form
    137.60/206.14 = 86.30/x
  3. Step 3: Cross multiply
    137.60x = 206.14 × 86.30
  4. Step 4: Simplify right side
    137.60x = 17,789.88
  5. Step 5: Solve for x
    x = 17,789.88/137.60
  6. Step 6: Final answer
    x = 129.29

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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.