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Finding the Fourth Proportional to 640.04, 958.54 and 408.20

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Solution

The fourth proportional to 640.04, 958.54 and 408.20 is: 611.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.04 : 958.54 = 408.20 : x
  2. Step 2: Convert to fraction form
    640.04/958.54 = 408.20/x
  3. Step 3: Cross multiply
    640.04x = 958.54 × 408.20
  4. Step 4: Simplify right side
    640.04x = 391,276.03
  5. Step 5: Solve for x
    x = 391,276.03/640.04
  6. Step 6: Final answer
    x = 611.33

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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.