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Finding the Fourth Proportional to 408.42, 612.69 and 225.75

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Solution

The fourth proportional to 408.42, 612.69 and 225.75 is: 338.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.42 : 612.69 = 225.75 : x
  2. Step 2: Convert to fraction form
    408.42/612.69 = 225.75/x
  3. Step 3: Cross multiply
    408.42x = 612.69 × 225.75
  4. Step 4: Simplify right side
    408.42x = 138,314.77
  5. Step 5: Solve for x
    x = 138,314.77/408.42
  6. Step 6: Final answer
    x = 338.66

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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.