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Finding the Fourth Proportional to 639.56, 882.45 and 359.78

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Solution

The fourth proportional to 639.56, 882.45 and 359.78 is: 496.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.56 : 882.45 = 359.78 : x
  2. Step 2: Convert to fraction form
    639.56/882.45 = 359.78/x
  3. Step 3: Cross multiply
    639.56x = 882.45 × 359.78
  4. Step 4: Simplify right side
    639.56x = 317,490.07
  5. Step 5: Solve for x
    x = 317,490.07/639.56
  6. Step 6: Final answer
    x = 496.42

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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.