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Finding the Fourth Proportional to 820.11, 1,230.17 and 203.81

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Solution

The fourth proportional to 820.11, 1,230.17 and 203.81 is: 305.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.11 : 1,230.17 = 203.81 : x
  2. Step 2: Convert to fraction form
    820.11/1,230.17 = 203.81/x
  3. Step 3: Cross multiply
    820.11x = 1,230.17 × 203.81
  4. Step 4: Simplify right side
    820.11x = 250,723.00
  5. Step 5: Solve for x
    x = 250,723.00/820.11
  6. Step 6: Final answer
    x = 305.72

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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.