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Finding the Fourth Proportional to 644.31, 966.78 and 400.77

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Solution

The fourth proportional to 644.31, 966.78 and 400.77 is: 601.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.31 : 966.78 = 400.77 : x
  2. Step 2: Convert to fraction form
    644.31/966.78 = 400.77/x
  3. Step 3: Cross multiply
    644.31x = 966.78 × 400.77
  4. Step 4: Simplify right side
    644.31x = 387,456.42
  5. Step 5: Solve for x
    x = 387,456.42/644.31
  6. Step 6: Final answer
    x = 601.35

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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.