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Finding the Fourth Proportional to 137.97, 207.09 and 86.71

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Solution

The fourth proportional to 137.97, 207.09 and 86.71 is: 130.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.97 : 207.09 = 86.71 : x
  2. Step 2: Convert to fraction form
    137.97/207.09 = 86.71/x
  3. Step 3: Cross multiply
    137.97x = 207.09 × 86.71
  4. Step 4: Simplify right side
    137.97x = 17,956.77
  5. Step 5: Solve for x
    x = 17,956.77/137.97
  6. Step 6: Final answer
    x = 130.15

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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.