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Finding the Fourth Proportional to 331.20, 456.80 and 287.36

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Solution

The fourth proportional to 331.20, 456.80 and 287.36 is: 396.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    331.20 : 456.80 = 287.36 : x
  2. Step 2: Convert to fraction form
    331.20/456.80 = 287.36/x
  3. Step 3: Cross multiply
    331.20x = 456.80 × 287.36
  4. Step 4: Simplify right side
    331.20x = 131,266.05
  5. Step 5: Solve for x
    x = 131,266.05/331.20
  6. Step 6: Final answer
    x = 396.33

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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.