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Finding the Fourth Proportional to 138.09, 191.47 and 130.80

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Solution

The fourth proportional to 138.09, 191.47 and 130.80 is: 181.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.09 : 191.47 = 130.80 : x
  2. Step 2: Convert to fraction form
    138.09/191.47 = 130.80/x
  3. Step 3: Cross multiply
    138.09x = 191.47 × 130.80
  4. Step 4: Simplify right side
    138.09x = 25,044.28
  5. Step 5: Solve for x
    x = 25,044.28/138.09
  6. Step 6: Final answer
    x = 181.36

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.