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Finding the Fourth Proportional to 639.10, 959.55 and 396.10

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Solution

The fourth proportional to 639.10, 959.55 and 396.10 is: 594.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.10 : 959.55 = 396.10 : x
  2. Step 2: Convert to fraction form
    639.10/959.55 = 396.10/x
  3. Step 3: Cross multiply
    639.10x = 959.55 × 396.10
  4. Step 4: Simplify right side
    639.10x = 380,077.76
  5. Step 5: Solve for x
    x = 380,077.76/639.10
  6. Step 6: Final answer
    x = 594.71

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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.