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Finding the Fourth Proportional to 681.07, 1,020.82 and 315.09

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Solution

The fourth proportional to 681.07, 1,020.82 and 315.09 is: 472.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.07 : 1,020.82 = 315.09 : x
  2. Step 2: Convert to fraction form
    681.07/1,020.82 = 315.09/x
  3. Step 3: Cross multiply
    681.07x = 1,020.82 × 315.09
  4. Step 4: Simplify right side
    681.07x = 321,650.17
  5. Step 5: Solve for x
    x = 321,650.17/681.07
  6. Step 6: Final answer
    x = 472.27

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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.