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Finding the Fourth Proportional to 639.71, 882.28 and 451.28

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Solution

The fourth proportional to 639.71, 882.28 and 451.28 is: 622.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.71 : 882.28 = 451.28 : x
  2. Step 2: Convert to fraction form
    639.71/882.28 = 451.28/x
  3. Step 3: Cross multiply
    639.71x = 882.28 × 451.28
  4. Step 4: Simplify right side
    639.71x = 398,153.07
  5. Step 5: Solve for x
    x = 398,153.07/639.71
  6. Step 6: Final answer
    x = 622.39

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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.