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Finding the Fourth Proportional to 139.31, 192.26 and 81.10

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Solution

The fourth proportional to 139.31, 192.26 and 81.10 is: 111.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.31 : 192.26 = 81.10 : x
  2. Step 2: Convert to fraction form
    139.31/192.26 = 81.10/x
  3. Step 3: Cross multiply
    139.31x = 192.26 × 81.10
  4. Step 4: Simplify right side
    139.31x = 15,592.29
  5. Step 5: Solve for x
    x = 15,592.29/139.31
  6. Step 6: Final answer
    x = 111.93

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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.