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Finding the Fourth Proportional to 72.12, 107.92 and 67.29

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Solution

The fourth proportional to 72.12, 107.92 and 67.29 is: 100.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.12 : 107.92 = 67.29 : x
  2. Step 2: Convert to fraction form
    72.12/107.92 = 67.29/x
  3. Step 3: Cross multiply
    72.12x = 107.92 × 67.29
  4. Step 4: Simplify right side
    72.12x = 7,261.54
  5. Step 5: Solve for x
    x = 7,261.54/72.12
  6. Step 6: Final answer
    x = 100.69

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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.