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Finding the Fourth Proportional to 408.85, 612.25 and 316.78

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Solution

The fourth proportional to 408.85, 612.25 and 316.78 is: 474.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.85 : 612.25 = 316.78 : x
  2. Step 2: Convert to fraction form
    408.85/612.25 = 316.78/x
  3. Step 3: Cross multiply
    408.85x = 612.25 × 316.78
  4. Step 4: Simplify right side
    408.85x = 193,948.56
  5. Step 5: Solve for x
    x = 193,948.56/408.85
  6. Step 6: Final answer
    x = 474.38

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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.