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Finding the Fourth Proportional to 146.87, 219.47 and 128.42

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Solution

The fourth proportional to 146.87, 219.47 and 128.42 is: 191.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    146.87 : 219.47 = 128.42 : x
  2. Step 2: Convert to fraction form
    146.87/219.47 = 128.42/x
  3. Step 3: Cross multiply
    146.87x = 219.47 × 128.42
  4. Step 4: Simplify right side
    146.87x = 28,183.56
  5. Step 5: Solve for x
    x = 28,183.56/146.87
  6. Step 6: Final answer
    x = 191.90

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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.