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Finding the Fourth Proportional to 819.68, 1,228.48 and 408.96

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Solution

The fourth proportional to 819.68, 1,228.48 and 408.96 is: 612.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.68 : 1,228.48 = 408.96 : x
  2. Step 2: Convert to fraction form
    819.68/1,228.48 = 408.96/x
  3. Step 3: Cross multiply
    819.68x = 1,228.48 × 408.96
  4. Step 4: Simplify right side
    819.68x = 502,399.18
  5. Step 5: Solve for x
    x = 502,399.18/819.68
  6. Step 6: Final answer
    x = 612.92

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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.