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Finding the Fourth Proportional to 138.31, 207.56 and 83.63

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Solution

The fourth proportional to 138.31, 207.56 and 83.63 is: 125.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.31 : 207.56 = 83.63 : x
  2. Step 2: Convert to fraction form
    138.31/207.56 = 83.63/x
  3. Step 3: Cross multiply
    138.31x = 207.56 × 83.63
  4. Step 4: Simplify right side
    138.31x = 17,358.97
  5. Step 5: Solve for x
    x = 17,358.97/138.31
  6. Step 6: Final answer
    x = 125.51

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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.