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Finding the Fourth Proportional to 644.57, 966.89 and 319.85

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Solution

The fourth proportional to 644.57, 966.89 and 319.85 is: 479.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.57 : 966.89 = 319.85 : x
  2. Step 2: Convert to fraction form
    644.57/966.89 = 319.85/x
  3. Step 3: Cross multiply
    644.57x = 966.89 × 319.85
  4. Step 4: Simplify right side
    644.57x = 309,254.93
  5. Step 5: Solve for x
    x = 309,254.93/644.57
  6. Step 6: Final answer
    x = 479.79

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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.