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Finding the Fourth Proportional to 137.79, 190.32 and 102.87

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Solution

The fourth proportional to 137.79, 190.32 and 102.87 is: 142.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.79 : 190.32 = 102.87 : x
  2. Step 2: Convert to fraction form
    137.79/190.32 = 102.87/x
  3. Step 3: Cross multiply
    137.79x = 190.32 × 102.87
  4. Step 4: Simplify right side
    137.79x = 19,578.22
  5. Step 5: Solve for x
    x = 19,578.22/137.79
  6. Step 6: Final answer
    x = 142.09

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.