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Finding the Fourth Proportional to 638.42, 879.98 and 527.72

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Solution

The fourth proportional to 638.42, 879.98 and 527.72 is: 727.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.42 : 879.98 = 527.72 : x
  2. Step 2: Convert to fraction form
    638.42/879.98 = 527.72/x
  3. Step 3: Cross multiply
    638.42x = 879.98 × 527.72
  4. Step 4: Simplify right side
    638.42x = 464,376.01
  5. Step 5: Solve for x
    x = 464,376.01/638.42
  6. Step 6: Final answer
    x = 727.39

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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.