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Finding the Fourth Proportional to 311.01, 428.67 and 284.86

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Solution

The fourth proportional to 311.01, 428.67 and 284.86 is: 392.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.01 : 428.67 = 284.86 : x
  2. Step 2: Convert to fraction form
    311.01/428.67 = 284.86/x
  3. Step 3: Cross multiply
    311.01x = 428.67 × 284.86
  4. Step 4: Simplify right side
    311.01x = 122,110.94
  5. Step 5: Solve for x
    x = 122,110.94/311.01
  6. Step 6: Final answer
    x = 392.63

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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.