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Finding the Fourth Proportional to 408.95, 613.78 and 287.35

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Solution

The fourth proportional to 408.95, 613.78 and 287.35 is: 431.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.95 : 613.78 = 287.35 : x
  2. Step 2: Convert to fraction form
    408.95/613.78 = 287.35/x
  3. Step 3: Cross multiply
    408.95x = 613.78 × 287.35
  4. Step 4: Simplify right side
    408.95x = 176,367.43
  5. Step 5: Solve for x
    x = 176,367.43/408.95
  6. Step 6: Final answer
    x = 431.27

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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.