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Finding the Fourth Proportional to 644.80, 966.54 and 279.28

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Solution

The fourth proportional to 644.80, 966.54 and 279.28 is: 418.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.80 : 966.54 = 279.28 : x
  2. Step 2: Convert to fraction form
    644.80/966.54 = 279.28/x
  3. Step 3: Cross multiply
    644.80x = 966.54 × 279.28
  4. Step 4: Simplify right side
    644.80x = 269,935.29
  5. Step 5: Solve for x
    x = 269,935.29/644.80
  6. Step 6: Final answer
    x = 418.63

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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.