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Finding the Fourth Proportional to 331.40, 456.15 and 289.85

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Solution

The fourth proportional to 331.40, 456.15 and 289.85 is: 398.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    331.40 : 456.15 = 289.85 : x
  2. Step 2: Convert to fraction form
    331.40/456.15 = 289.85/x
  3. Step 3: Cross multiply
    331.40x = 456.15 × 289.85
  4. Step 4: Simplify right side
    331.40x = 132,212.80
  5. Step 5: Solve for x
    x = 132,212.80/331.40
  6. Step 6: Final answer
    x = 398.96

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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.