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Finding the Fourth Proportional to 138.10, 206.98 and 56.92

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Solution

The fourth proportional to 138.10, 206.98 and 56.92 is: 85.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.10 : 206.98 = 56.92 : x
  2. Step 2: Convert to fraction form
    138.10/206.98 = 56.92/x
  3. Step 3: Cross multiply
    138.10x = 206.98 × 56.92
  4. Step 4: Simplify right side
    138.10x = 11,781.30
  5. Step 5: Solve for x
    x = 11,781.30/138.10
  6. Step 6: Final answer
    x = 85.31

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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.