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Finding the Fourth Proportional to 800.05, 1,200.08 and 408.95

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Solution

The fourth proportional to 800.05, 1,200.08 and 408.95 is: 613.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.05 : 1,200.08 = 408.95 : x
  2. Step 2: Convert to fraction form
    800.05/1,200.08 = 408.95/x
  3. Step 3: Cross multiply
    800.05x = 1,200.08 × 408.95
  4. Step 4: Simplify right side
    800.05x = 490,766.72
  5. Step 5: Solve for x
    x = 490,766.72/800.05
  6. Step 6: Final answer
    x = 613.42

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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.