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Finding the Fourth Proportional to 638.25, 880.56 and 389.67

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Solution

The fourth proportional to 638.25, 880.56 and 389.67 is: 537.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.25 : 880.56 = 389.67 : x
  2. Step 2: Convert to fraction form
    638.25/880.56 = 389.67/x
  3. Step 3: Cross multiply
    638.25x = 880.56 × 389.67
  4. Step 4: Simplify right side
    638.25x = 343,127.82
  5. Step 5: Solve for x
    x = 343,127.82/638.25
  6. Step 6: Final answer
    x = 537.61

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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.