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Finding the Fourth Proportional to 638.31, 880.70 and 389.62

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Solution

The fourth proportional to 638.31, 880.70 and 389.62 is: 537.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.31 : 880.70 = 389.62 : x
  2. Step 2: Convert to fraction form
    638.31/880.70 = 389.62/x
  3. Step 3: Cross multiply
    638.31x = 880.70 × 389.62
  4. Step 4: Simplify right side
    638.31x = 343,133.93
  5. Step 5: Solve for x
    x = 343,133.93/638.31
  6. Step 6: Final answer
    x = 537.57

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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.