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Finding the Fourth Proportional to 638.58, 879.90 and 605.64

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Solution

The fourth proportional to 638.58, 879.90 and 605.64 is: 834.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.58 : 879.90 = 605.64 : x
  2. Step 2: Convert to fraction form
    638.58/879.90 = 605.64/x
  3. Step 3: Cross multiply
    638.58x = 879.90 × 605.64
  4. Step 4: Simplify right side
    638.58x = 532,902.64
  5. Step 5: Solve for x
    x = 532,902.64/638.58
  6. Step 6: Final answer
    x = 834.51

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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.