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Finding the Fourth Proportional to 645.05, 966.80 and 279.43

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Solution

The fourth proportional to 645.05, 966.80 and 279.43 is: 418.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.05 : 966.80 = 279.43 : x
  2. Step 2: Convert to fraction form
    645.05/966.80 = 279.43/x
  3. Step 3: Cross multiply
    645.05x = 966.80 × 279.43
  4. Step 4: Simplify right side
    645.05x = 270,151.21
  5. Step 5: Solve for x
    x = 270,151.21/645.05
  6. Step 6: Final answer
    x = 418.80

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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.