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Finding the Fourth Proportional to 571.78, 789.11 and 489.16

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Solution

The fourth proportional to 571.78, 789.11 and 489.16 is: 675.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    571.78 : 789.11 = 489.16 : x
  2. Step 2: Convert to fraction form
    571.78/789.11 = 489.16/x
  3. Step 3: Cross multiply
    571.78x = 789.11 × 489.16
  4. Step 4: Simplify right side
    571.78x = 386,001.05
  5. Step 5: Solve for x
    x = 386,001.05/571.78
  6. Step 6: Final answer
    x = 675.09

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.