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Finding the Fourth Proportional to 12.56, 17.31 and 8.91

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Solution

The fourth proportional to 12.56, 17.31 and 8.91 is: 12.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    12.56 : 17.31 = 8.91 : x
  2. Step 2: Convert to fraction form
    12.56/17.31 = 8.91/x
  3. Step 3: Cross multiply
    12.56x = 17.31 × 8.91
  4. Step 4: Simplify right side
    12.56x = 154.27
  5. Step 5: Solve for x
    x = 154.27/12.56
  6. Step 6: Final answer
    x = 12.29

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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.