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Finding the Fourth Proportional to 640.08, 959.51 and 408.32

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Solution

The fourth proportional to 640.08, 959.51 and 408.32 is: 612.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.08 : 959.51 = 408.32 : x
  2. Step 2: Convert to fraction form
    640.08/959.51 = 408.32/x
  3. Step 3: Cross multiply
    640.08x = 959.51 × 408.32
  4. Step 4: Simplify right side
    640.08x = 391,787.12
  5. Step 5: Solve for x
    x = 391,787.12/640.08
  6. Step 6: Final answer
    x = 612.09

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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.