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Finding the Fourth Proportional to 639.38, 960.29 and 397.59

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Solution

The fourth proportional to 639.38, 960.29 and 397.59 is: 597.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.38 : 960.29 = 397.59 : x
  2. Step 2: Convert to fraction form
    639.38/960.29 = 397.59/x
  3. Step 3: Cross multiply
    639.38x = 960.29 × 397.59
  4. Step 4: Simplify right side
    639.38x = 381,803.31
  5. Step 5: Solve for x
    x = 381,803.31/639.38
  6. Step 6: Final answer
    x = 597.15

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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.