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Finding the Fourth Proportional to 311.89, 430.26 and 201.31

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Solution

The fourth proportional to 311.89, 430.26 and 201.31 is: 277.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.89 : 430.26 = 201.31 : x
  2. Step 2: Convert to fraction form
    311.89/430.26 = 201.31/x
  3. Step 3: Cross multiply
    311.89x = 430.26 × 201.31
  4. Step 4: Simplify right side
    311.89x = 86,615.64
  5. Step 5: Solve for x
    x = 86,615.64/311.89
  6. Step 6: Final answer
    x = 277.71

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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.