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Finding the Fourth Proportional to 680.12, 1,020.45 and 636.38

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Solution

The fourth proportional to 680.12, 1,020.45 and 636.38 is: 954.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.12 : 1,020.45 = 636.38 : x
  2. Step 2: Convert to fraction form
    680.12/1,020.45 = 636.38/x
  3. Step 3: Cross multiply
    680.12x = 1,020.45 × 636.38
  4. Step 4: Simplify right side
    680.12x = 649,393.97
  5. Step 5: Solve for x
    x = 649,393.97/680.12
  6. Step 6: Final answer
    x = 954.82

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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.