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Finding the Fourth Proportional to 79.14, 118.15 and 68.90

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Solution

The fourth proportional to 79.14, 118.15 and 68.90 is: 102.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.14 : 118.15 = 68.90 : x
  2. Step 2: Convert to fraction form
    79.14/118.15 = 68.90/x
  3. Step 3: Cross multiply
    79.14x = 118.15 × 68.90
  4. Step 4: Simplify right side
    79.14x = 8,140.54
  5. Step 5: Solve for x
    x = 8,140.54/79.14
  6. Step 6: Final answer
    x = 102.86

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.