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Finding the Fourth Proportional to 639.30, 882.20 and 359.54

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Solution

The fourth proportional to 639.30, 882.20 and 359.54 is: 496.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.30 : 882.20 = 359.54 : x
  2. Step 2: Convert to fraction form
    639.30/882.20 = 359.54/x
  3. Step 3: Cross multiply
    639.30x = 882.20 × 359.54
  4. Step 4: Simplify right side
    639.30x = 317,186.19
  5. Step 5: Solve for x
    x = 317,186.19/639.30
  6. Step 6: Final answer
    x = 496.15

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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.