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Finding the Fourth Proportional to 636.41, 878.62 and 485.86

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Solution

The fourth proportional to 636.41, 878.62 and 485.86 is: 670.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    636.41 : 878.62 = 485.86 : x
  2. Step 2: Convert to fraction form
    636.41/878.62 = 485.86/x
  3. Step 3: Cross multiply
    636.41x = 878.62 × 485.86
  4. Step 4: Simplify right side
    636.41x = 426,882.90
  5. Step 5: Solve for x
    x = 426,882.90/636.41
  6. Step 6: Final answer
    x = 670.76

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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.