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Finding the Fourth Proportional to 138.21, 207.27 and 57.08

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Solution

The fourth proportional to 138.21, 207.27 and 57.08 is: 85.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.21 : 207.27 = 57.08 : x
  2. Step 2: Convert to fraction form
    138.21/207.27 = 57.08/x
  3. Step 3: Cross multiply
    138.21x = 207.27 × 57.08
  4. Step 4: Simplify right side
    138.21x = 11,829.94
  5. Step 5: Solve for x
    x = 11,829.94/138.21
  6. Step 6: Final answer
    x = 85.59

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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.