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Finding the Fourth Proportional to 638.33, 956.35 and 387.71

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Solution

The fourth proportional to 638.33, 956.35 and 387.71 is: 580.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.33 : 956.35 = 387.71 : x
  2. Step 2: Convert to fraction form
    638.33/956.35 = 387.71/x
  3. Step 3: Cross multiply
    638.33x = 956.35 × 387.71
  4. Step 4: Simplify right side
    638.33x = 370,780.71
  5. Step 5: Solve for x
    x = 370,780.71/638.33
  6. Step 6: Final answer
    x = 580.87

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.