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Finding the Fourth Proportional to 812.20, 1,218.30 and 401.62

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Solution

The fourth proportional to 812.20, 1,218.30 and 401.62 is: 602.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.20 : 1,218.30 = 401.62 : x
  2. Step 2: Convert to fraction form
    812.20/1,218.30 = 401.62/x
  3. Step 3: Cross multiply
    812.20x = 1,218.30 × 401.62
  4. Step 4: Simplify right side
    812.20x = 489,293.65
  5. Step 5: Solve for x
    x = 489,293.65/812.20
  6. Step 6: Final answer
    x = 602.43

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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.