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Finding the Fourth Proportional to 97.09, 133.86 and 78.61

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Solution

The fourth proportional to 97.09, 133.86 and 78.61 is: 108.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    97.09 : 133.86 = 78.61 : x
  2. Step 2: Convert to fraction form
    97.09/133.86 = 78.61/x
  3. Step 3: Cross multiply
    97.09x = 133.86 × 78.61
  4. Step 4: Simplify right side
    97.09x = 10,522.73
  5. Step 5: Solve for x
    x = 10,522.73/97.09
  6. Step 6: Final answer
    x = 108.38

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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.