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Finding the Fourth Proportional to 639.13, 959.91 and 397.35

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Solution

The fourth proportional to 639.13, 959.91 and 397.35 is: 596.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.13 : 959.91 = 397.35 : x
  2. Step 2: Convert to fraction form
    639.13/959.91 = 397.35/x
  3. Step 3: Cross multiply
    639.13x = 959.91 × 397.35
  4. Step 4: Simplify right side
    639.13x = 381,415.44
  5. Step 5: Solve for x
    x = 381,415.44/639.13
  6. Step 6: Final answer
    x = 596.77

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.