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Finding the Fourth Proportional to 812.14, 1,218.21 and 401.79

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Solution

The fourth proportional to 812.14, 1,218.21 and 401.79 is: 602.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.14 : 1,218.21 = 401.79 : x
  2. Step 2: Convert to fraction form
    812.14/1,218.21 = 401.79/x
  3. Step 3: Cross multiply
    812.14x = 1,218.21 × 401.79
  4. Step 4: Simplify right side
    812.14x = 489,464.60
  5. Step 5: Solve for x
    x = 489,464.60/812.14
  6. Step 6: Final answer
    x = 602.69

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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.