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Finding the Fourth Proportional to 645.28, 967.05 and 279.55

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Solution

The fourth proportional to 645.28, 967.05 and 279.55 is: 418.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.28 : 967.05 = 279.55 : x
  2. Step 2: Convert to fraction form
    645.28/967.05 = 279.55/x
  3. Step 3: Cross multiply
    645.28x = 967.05 × 279.55
  4. Step 4: Simplify right side
    645.28x = 270,338.83
  5. Step 5: Solve for x
    x = 270,338.83/645.28
  6. Step 6: Final answer
    x = 418.95

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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.