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Finding the Fourth Proportional to 198.90, 298.44 and 102.78

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Solution

The fourth proportional to 198.90, 298.44 and 102.78 is: 154.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    198.90 : 298.44 = 102.78 : x
  2. Step 2: Convert to fraction form
    198.90/298.44 = 102.78/x
  3. Step 3: Cross multiply
    198.90x = 298.44 × 102.78
  4. Step 4: Simplify right side
    198.90x = 30,673.66
  5. Step 5: Solve for x
    x = 30,673.66/198.90
  6. Step 6: Final answer
    x = 154.22

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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.