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Finding the Fourth Proportional to 665.81, 998.78 and 255.29

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Solution

The fourth proportional to 665.81, 998.78 and 255.29 is: 382.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.81 : 998.78 = 255.29 : x
  2. Step 2: Convert to fraction form
    665.81/998.78 = 255.29/x
  3. Step 3: Cross multiply
    665.81x = 998.78 × 255.29
  4. Step 4: Simplify right side
    665.81x = 254,976.05
  5. Step 5: Solve for x
    x = 254,976.05/665.81
  6. Step 6: Final answer
    x = 382.96

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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.