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Finding the Fourth Proportional to 819.12, 1,228.56 and 299.10

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Solution

The fourth proportional to 819.12, 1,228.56 and 299.10 is: 448.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.12 : 1,228.56 = 299.10 : x
  2. Step 2: Convert to fraction form
    819.12/1,228.56 = 299.10/x
  3. Step 3: Cross multiply
    819.12x = 1,228.56 × 299.10
  4. Step 4: Simplify right side
    819.12x = 367,462.30
  5. Step 5: Solve for x
    x = 367,462.30/819.12
  6. Step 6: Final answer
    x = 448.61

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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.