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Finding the Fourth Proportional to 660.90, 911.97 and 381.09

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Solution

The fourth proportional to 660.90, 911.97 and 381.09 is: 525.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.90 : 911.97 = 381.09 : x
  2. Step 2: Convert to fraction form
    660.90/911.97 = 381.09/x
  3. Step 3: Cross multiply
    660.90x = 911.97 × 381.09
  4. Step 4: Simplify right side
    660.90x = 347,542.65
  5. Step 5: Solve for x
    x = 347,542.65/660.90
  6. Step 6: Final answer
    x = 525.86

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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.