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Finding the Fourth Proportional to 820.38, 1,132.12 and 489.06

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Solution

The fourth proportional to 820.38, 1,132.12 and 489.06 is: 674.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.38 : 1,132.12 = 489.06 : x
  2. Step 2: Convert to fraction form
    820.38/1,132.12 = 489.06/x
  3. Step 3: Cross multiply
    820.38x = 1,132.12 × 489.06
  4. Step 4: Simplify right side
    820.38x = 553,674.61
  5. Step 5: Solve for x
    x = 553,674.61/820.38
  6. Step 6: Final answer
    x = 674.90

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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.