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Finding the Fourth Proportional to 820.11, 1,227.10 and 489.84

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Solution

The fourth proportional to 820.11, 1,227.10 and 489.84 is: 732.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.11 : 1,227.10 = 489.84 : x
  2. Step 2: Convert to fraction form
    820.11/1,227.10 = 489.84/x
  3. Step 3: Cross multiply
    820.11x = 1,227.10 × 489.84
  4. Step 4: Simplify right side
    820.11x = 601,082.66
  5. Step 5: Solve for x
    x = 601,082.66/820.11
  6. Step 6: Final answer
    x = 732.93

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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.