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Finding the Fourth Proportional to 20.09, 30.08 and 13.56

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Solution

The fourth proportional to 20.09, 30.08 and 13.56 is: 20.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.09 : 30.08 = 13.56 : x
  2. Step 2: Convert to fraction form
    20.09/30.08 = 13.56/x
  3. Step 3: Cross multiply
    20.09x = 30.08 × 13.56
  4. Step 4: Simplify right side
    20.09x = 407.88
  5. Step 5: Solve for x
    x = 407.88/20.09
  6. Step 6: Final answer
    x = 20.30

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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.