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Finding the Fourth Proportional to 412.29, 618.50 and 219.81

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Solution

The fourth proportional to 412.29, 618.50 and 219.81 is: 329.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.29 : 618.50 = 219.81 : x
  2. Step 2: Convert to fraction form
    412.29/618.50 = 219.81/x
  3. Step 3: Cross multiply
    412.29x = 618.50 × 219.81
  4. Step 4: Simplify right side
    412.29x = 135,951.39
  5. Step 5: Solve for x
    x = 135,951.39/412.29
  6. Step 6: Final answer
    x = 329.75

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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.