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Finding the Fourth Proportional to 137.07, 205.79 and 85.54

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Solution

The fourth proportional to 137.07, 205.79 and 85.54 is: 128.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.07 : 205.79 = 85.54 : x
  2. Step 2: Convert to fraction form
    137.07/205.79 = 85.54/x
  3. Step 3: Cross multiply
    137.07x = 205.79 × 85.54
  4. Step 4: Simplify right side
    137.07x = 17,603.28
  5. Step 5: Solve for x
    x = 17,603.28/137.07
  6. Step 6: Final answer
    x = 128.43

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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.