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Finding the Fourth Proportional to 15.13, 20.87 and 10.81

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Solution

The fourth proportional to 15.13, 20.87 and 10.81 is: 14.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    15.13 : 20.87 = 10.81 : x
  2. Step 2: Convert to fraction form
    15.13/20.87 = 10.81/x
  3. Step 3: Cross multiply
    15.13x = 20.87 × 10.81
  4. Step 4: Simplify right side
    15.13x = 225.55
  5. Step 5: Solve for x
    x = 225.55/15.13
  6. Step 6: Final answer
    x = 14.91

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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.