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Finding the Fourth Proportional to 639.30, 880.39 and 442.47

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Solution

The fourth proportional to 639.30, 880.39 and 442.47 is: 609.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.30 : 880.39 = 442.47 : x
  2. Step 2: Convert to fraction form
    639.30/880.39 = 442.47/x
  3. Step 3: Cross multiply
    639.30x = 880.39 × 442.47
  4. Step 4: Simplify right side
    639.30x = 389,546.16
  5. Step 5: Solve for x
    x = 389,546.16/639.30
  6. Step 6: Final answer
    x = 609.33

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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.