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Finding the Fourth Proportional to 485.35, 728.17 and 408.49

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Solution

The fourth proportional to 485.35, 728.17 and 408.49 is: 612.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.35 : 728.17 = 408.49 : x
  2. Step 2: Convert to fraction form
    485.35/728.17 = 408.49/x
  3. Step 3: Cross multiply
    485.35x = 728.17 × 408.49
  4. Step 4: Simplify right side
    485.35x = 297,447.32
  5. Step 5: Solve for x
    x = 297,447.32/485.35
  6. Step 6: Final answer
    x = 612.85

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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.