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Finding the Fourth Proportional to 638.38, 881.47 and 513.64

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Solution

The fourth proportional to 638.38, 881.47 and 513.64 is: 709.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.38 : 881.47 = 513.64 : x
  2. Step 2: Convert to fraction form
    638.38/881.47 = 513.64/x
  3. Step 3: Cross multiply
    638.38x = 881.47 × 513.64
  4. Step 4: Simplify right side
    638.38x = 452,758.25
  5. Step 5: Solve for x
    x = 452,758.25/638.38
  6. Step 6: Final answer
    x = 709.23

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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.