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Finding the Fourth Proportional to 639.72, 958.37 and 379.17

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Solution

The fourth proportional to 639.72, 958.37 and 379.17 is: 568.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.72 : 958.37 = 379.17 : x
  2. Step 2: Convert to fraction form
    639.72/958.37 = 379.17/x
  3. Step 3: Cross multiply
    639.72x = 958.37 × 379.17
  4. Step 4: Simplify right side
    639.72x = 363,383.26
  5. Step 5: Solve for x
    x = 363,383.26/639.72
  6. Step 6: Final answer
    x = 568.03

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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.