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Finding the Fourth Proportional to 639.46, 958.92 and 379.72

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Solution

The fourth proportional to 639.46, 958.92 and 379.72 is: 569.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.46 : 958.92 = 379.72 : x
  2. Step 2: Convert to fraction form
    639.46/958.92 = 379.72/x
  3. Step 3: Cross multiply
    639.46x = 958.92 × 379.72
  4. Step 4: Simplify right side
    639.46x = 364,121.10
  5. Step 5: Solve for x
    x = 364,121.10/639.46
  6. Step 6: Final answer
    x = 569.42

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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.