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Finding the Fourth Proportional to 681.20, 1,021.80 and 635.30

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Solution

The fourth proportional to 681.20, 1,021.80 and 635.30 is: 952.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.20 : 1,021.80 = 635.30 : x
  2. Step 2: Convert to fraction form
    681.20/1,021.80 = 635.30/x
  3. Step 3: Cross multiply
    681.20x = 1,021.80 × 635.30
  4. Step 4: Simplify right side
    681.20x = 649,149.54
  5. Step 5: Solve for x
    x = 649,149.54/681.20
  6. Step 6: Final answer
    x = 952.95

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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.