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Finding the Fourth Proportional to 723.72, 996.20 and 640.68

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Solution

The fourth proportional to 723.72, 996.20 and 640.68 is: 881.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    723.72 : 996.20 = 640.68 : x
  2. Step 2: Convert to fraction form
    723.72/996.20 = 640.68/x
  3. Step 3: Cross multiply
    723.72x = 996.20 × 640.68
  4. Step 4: Simplify right side
    723.72x = 638,242.21
  5. Step 5: Solve for x
    x = 638,242.21/723.72
  6. Step 6: Final answer
    x = 881.89

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.