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Finding the Fourth Proportional to 819.65, 1,229.99 and 299.60

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Solution

The fourth proportional to 819.65, 1,229.99 and 299.60 is: 449.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.65 : 1,229.99 = 299.60 : x
  2. Step 2: Convert to fraction form
    819.65/1,229.99 = 299.60/x
  3. Step 3: Cross multiply
    819.65x = 1,229.99 × 299.60
  4. Step 4: Simplify right side
    819.65x = 368,505.00
  5. Step 5: Solve for x
    x = 368,505.00/819.65
  6. Step 6: Final answer
    x = 449.59

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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.