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Finding the Fourth Proportional to 198.90, 298.20 and 107.70

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Solution

The fourth proportional to 198.90, 298.20 and 107.70 is: 161.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    198.90 : 298.20 = 107.70 : x
  2. Step 2: Convert to fraction form
    198.90/298.20 = 107.70/x
  3. Step 3: Cross multiply
    198.90x = 298.20 × 107.70
  4. Step 4: Simplify right side
    198.90x = 32,116.14
  5. Step 5: Solve for x
    x = 32,116.14/198.90
  6. Step 6: Final answer
    x = 161.47

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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.