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Finding the Fourth Proportional to 636.80, 878.10 and 440.42

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Solution

The fourth proportional to 636.80, 878.10 and 440.42 is: 607.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    636.80 : 878.10 = 440.42 : x
  2. Step 2: Convert to fraction form
    636.80/878.10 = 440.42/x
  3. Step 3: Cross multiply
    636.80x = 878.10 × 440.42
  4. Step 4: Simplify right side
    636.80x = 386,732.80
  5. Step 5: Solve for x
    x = 386,732.80/636.80
  6. Step 6: Final answer
    x = 607.31

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.