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Finding the Fourth Proportional to 640.26, 882.81 and 557.15

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Solution

The fourth proportional to 640.26, 882.81 and 557.15 is: 768.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.26 : 882.81 = 557.15 : x
  2. Step 2: Convert to fraction form
    640.26/882.81 = 557.15/x
  3. Step 3: Cross multiply
    640.26x = 882.81 × 557.15
  4. Step 4: Simplify right side
    640.26x = 491,853.18
  5. Step 5: Solve for x
    x = 491,853.18/640.26
  6. Step 6: Final answer
    x = 768.21

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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.