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Finding the Fourth Proportional to 311.87, 430.35 and 213.65

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Solution

The fourth proportional to 311.87, 430.35 and 213.65 is: 294.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.87 : 430.35 = 213.65 : x
  2. Step 2: Convert to fraction form
    311.87/430.35 = 213.65/x
  3. Step 3: Cross multiply
    311.87x = 430.35 × 213.65
  4. Step 4: Simplify right side
    311.87x = 91,942.13
  5. Step 5: Solve for x
    x = 91,942.13/311.87
  6. Step 6: Final answer
    x = 294.81

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.