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Finding the Fourth Proportional to 644.98, 967.86 and 279.78

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Solution

The fourth proportional to 644.98, 967.86 and 279.78 is: 419.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.98 : 967.86 = 279.78 : x
  2. Step 2: Convert to fraction form
    644.98/967.86 = 279.78/x
  3. Step 3: Cross multiply
    644.98x = 967.86 × 279.78
  4. Step 4: Simplify right side
    644.98x = 270,787.87
  5. Step 5: Solve for x
    x = 270,787.87/644.98
  6. Step 6: Final answer
    x = 419.84

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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.