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Finding the Fourth Proportional to 820.16, 1,230.20 and 203.85

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Solution

The fourth proportional to 820.16, 1,230.20 and 203.85 is: 305.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.16 : 1,230.20 = 203.85 : x
  2. Step 2: Convert to fraction form
    820.16/1,230.20 = 203.85/x
  3. Step 3: Cross multiply
    820.16x = 1,230.20 × 203.85
  4. Step 4: Simplify right side
    820.16x = 250,769.10
  5. Step 5: Solve for x
    x = 250,769.10/820.16
  6. Step 6: Final answer
    x = 305.76

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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.