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Finding the Fourth Proportional to 138.10, 190.59 and 105.29

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Solution

The fourth proportional to 138.10, 190.59 and 105.29 is: 145.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.10 : 190.59 = 105.29 : x
  2. Step 2: Convert to fraction form
    138.10/190.59 = 105.29/x
  3. Step 3: Cross multiply
    138.10x = 190.59 × 105.29
  4. Step 4: Simplify right side
    138.10x = 20,067.22
  5. Step 5: Solve for x
    x = 20,067.22/138.10
  6. Step 6: Final answer
    x = 145.31

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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.