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Finding the Fourth Proportional to 12.71, 18.98 and 11.87

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Solution

The fourth proportional to 12.71, 18.98 and 11.87 is: 17.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    12.71 : 18.98 = 11.87 : x
  2. Step 2: Convert to fraction form
    12.71/18.98 = 11.87/x
  3. Step 3: Cross multiply
    12.71x = 18.98 × 11.87
  4. Step 4: Simplify right side
    12.71x = 225.14
  5. Step 5: Solve for x
    x = 225.14/12.71
  6. Step 6: Final answer
    x = 17.71

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.