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Finding the Fourth Proportional to 640.20, 882.66 and 551.49

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Solution

The fourth proportional to 640.20, 882.66 and 551.49 is: 760.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.20 : 882.66 = 551.49 : x
  2. Step 2: Convert to fraction form
    640.20/882.66 = 551.49/x
  3. Step 3: Cross multiply
    640.20x = 882.66 × 551.49
  4. Step 4: Simplify right side
    640.20x = 486,778.16
  5. Step 5: Solve for x
    x = 486,778.16/640.20
  6. Step 6: Final answer
    x = 760.35

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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.