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Finding the Fourth Proportional to 20.15, 30.26 and 18.19

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Solution

The fourth proportional to 20.15, 30.26 and 18.19 is: 27.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.15 : 30.26 = 18.19 : x
  2. Step 2: Convert to fraction form
    20.15/30.26 = 18.19/x
  3. Step 3: Cross multiply
    20.15x = 30.26 × 18.19
  4. Step 4: Simplify right side
    20.15x = 550.43
  5. Step 5: Solve for x
    x = 550.43/20.15
  6. Step 6: Final answer
    x = 27.32

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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.