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Finding the Fourth Proportional to 127.38, 191.18 and 87.09

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Solution

The fourth proportional to 127.38, 191.18 and 87.09 is: 130.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    127.38 : 191.18 = 87.09 : x
  2. Step 2: Convert to fraction form
    127.38/191.18 = 87.09/x
  3. Step 3: Cross multiply
    127.38x = 191.18 × 87.09
  4. Step 4: Simplify right side
    127.38x = 16,649.87
  5. Step 5: Solve for x
    x = 16,649.87/127.38
  6. Step 6: Final answer
    x = 130.71

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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.