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Finding the Fourth Proportional to 343.20, 515.31 and 206.85

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Solution

The fourth proportional to 343.20, 515.31 and 206.85 is: 310.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    343.20 : 515.31 = 206.85 : x
  2. Step 2: Convert to fraction form
    343.20/515.31 = 206.85/x
  3. Step 3: Cross multiply
    343.20x = 515.31 × 206.85
  4. Step 4: Simplify right side
    343.20x = 106,591.87
  5. Step 5: Solve for x
    x = 106,591.87/343.20
  6. Step 6: Final answer
    x = 310.58

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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.