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Finding the Fourth Proportional to 665.98, 998.78 and 255.09

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Solution

The fourth proportional to 665.98, 998.78 and 255.09 is: 382.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.98 : 998.78 = 255.09 : x
  2. Step 2: Convert to fraction form
    665.98/998.78 = 255.09/x
  3. Step 3: Cross multiply
    665.98x = 998.78 × 255.09
  4. Step 4: Simplify right side
    665.98x = 254,774.73
  5. Step 5: Solve for x
    x = 254,774.73/665.98
  6. Step 6: Final answer
    x = 382.56

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.