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Finding the Fourth Proportional to 820.28, 1,229.32 and 299.79

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Solution

The fourth proportional to 820.28, 1,229.32 and 299.79 is: 449.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.28 : 1,229.32 = 299.79 : x
  2. Step 2: Convert to fraction form
    820.28/1,229.32 = 299.79/x
  3. Step 3: Cross multiply
    820.28x = 1,229.32 × 299.79
  4. Step 4: Simplify right side
    820.28x = 368,537.09
  5. Step 5: Solve for x
    x = 368,537.09/820.28
  6. Step 6: Final answer
    x = 449.28

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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.