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Finding the Fourth Proportional to 639.48, 882.56 and 442.65

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Solution

The fourth proportional to 639.48, 882.56 and 442.65 is: 610.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.48 : 882.56 = 442.65 : x
  2. Step 2: Convert to fraction form
    639.48/882.56 = 442.65/x
  3. Step 3: Cross multiply
    639.48x = 882.56 × 442.65
  4. Step 4: Simplify right side
    639.48x = 390,665.18
  5. Step 5: Solve for x
    x = 390,665.18/639.48
  6. Step 6: Final answer
    x = 610.91

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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.