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Finding the Fourth Proportional to 812.91, 1,222.07 and 630.39

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Solution

The fourth proportional to 812.91, 1,222.07 and 630.39 is: 947.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.91 : 1,222.07 = 630.39 : x
  2. Step 2: Convert to fraction form
    812.91/1,222.07 = 630.39/x
  3. Step 3: Cross multiply
    812.91x = 1,222.07 × 630.39
  4. Step 4: Simplify right side
    812.91x = 770,377.56
  5. Step 5: Solve for x
    x = 770,377.56/812.91
  6. Step 6: Final answer
    x = 947.68

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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.