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Finding the Fourth Proportional to 15.00, 20.71 and 8.87

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Solution

The fourth proportional to 15.00, 20.71 and 8.87 is: 12.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    15.00 : 20.71 = 8.87 : x
  2. Step 2: Convert to fraction form
    15.00/20.71 = 8.87/x
  3. Step 3: Cross multiply
    15.00x = 20.71 × 8.87
  4. Step 4: Simplify right side
    15.00x = 183.56
  5. Step 5: Solve for x
    x = 183.56/15.00
  6. Step 6: Final answer
    x = 12.23

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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.