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Finding the Fourth Proportional to 640.60, 960.90 and 636.55

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Solution

The fourth proportional to 640.60, 960.90 and 636.55 is: 954.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.60 : 960.90 = 636.55 : x
  2. Step 2: Convert to fraction form
    640.60/960.90 = 636.55/x
  3. Step 3: Cross multiply
    640.60x = 960.90 × 636.55
  4. Step 4: Simplify right side
    640.60x = 611,660.90
  5. Step 5: Solve for x
    x = 611,660.90/640.60
  6. Step 6: Final answer
    x = 954.83

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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.