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Finding the Fourth Proportional to 2,638, 3,957 and 814

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Solution

The fourth proportional to 2,638, 3,957 and 814 is: 1,221

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,638 : 3,957 = 814 : x
  2. Step 2: Convert to fraction form
    2,638/3,957 = 814/x
  3. Step 3: Cross multiply
    2,638x = 3,957 × 814
  4. Step 4: Simplify right side
    2,638x = 3,220,998
  5. Step 5: Solve for x
    x = 3,220,998/2,638
  6. Step 6: Final answer
    x = 1,221

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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.