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Finding the Fourth Proportional to 640.63, 962.16 and 398.85

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Solution

The fourth proportional to 640.63, 962.16 and 398.85 is: 599.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.63 : 962.16 = 398.85 : x
  2. Step 2: Convert to fraction form
    640.63/962.16 = 398.85/x
  3. Step 3: Cross multiply
    640.63x = 962.16 × 398.85
  4. Step 4: Simplify right side
    640.63x = 383,757.52
  5. Step 5: Solve for x
    x = 383,757.52/640.63
  6. Step 6: Final answer
    x = 599.03

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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.