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Finding the Fourth Proportional to 311.78, 430.26 and 195.38

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Solution

The fourth proportional to 311.78, 430.26 and 195.38 is: 269.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.78 : 430.26 = 195.38 : x
  2. Step 2: Convert to fraction form
    311.78/430.26 = 195.38/x
  3. Step 3: Cross multiply
    311.78x = 430.26 × 195.38
  4. Step 4: Simplify right side
    311.78x = 84,064.20
  5. Step 5: Solve for x
    x = 84,064.20/311.78
  6. Step 6: Final answer
    x = 269.63

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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.