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Finding the Fourth Proportional to 638.72, 958.05 and 291.82

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Solution

The fourth proportional to 638.72, 958.05 and 291.82 is: 437.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.72 : 958.05 = 291.82 : x
  2. Step 2: Convert to fraction form
    638.72/958.05 = 291.82/x
  3. Step 3: Cross multiply
    638.72x = 958.05 × 291.82
  4. Step 4: Simplify right side
    638.72x = 279,578.15
  5. Step 5: Solve for x
    x = 279,578.15/638.72
  6. Step 6: Final answer
    x = 437.72

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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.