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Finding the Fourth Proportional to 821.08, 1,229.90 and 382.71

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Solution

The fourth proportional to 821.08, 1,229.90 and 382.71 is: 573.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    821.08 : 1,229.90 = 382.71 : x
  2. Step 2: Convert to fraction form
    821.08/1,229.90 = 382.71/x
  3. Step 3: Cross multiply
    821.08x = 1,229.90 × 382.71
  4. Step 4: Simplify right side
    821.08x = 470,697.01
  5. Step 5: Solve for x
    x = 470,697.01/821.08
  6. Step 6: Final answer
    x = 573.27

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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.