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Finding the Fourth Proportional to 639.68, 958.37 and 515.89

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Solution

The fourth proportional to 639.68, 958.37 and 515.89 is: 772.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.68 : 958.37 = 515.89 : x
  2. Step 2: Convert to fraction form
    639.68/958.37 = 515.89/x
  3. Step 3: Cross multiply
    639.68x = 958.37 × 515.89
  4. Step 4: Simplify right side
    639.68x = 494,408.52
  5. Step 5: Solve for x
    x = 494,408.52/639.68
  6. Step 6: Final answer
    x = 772.91

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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.