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Finding the Fourth Proportional to 18.15, 27.21 and 13.05

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Solution

The fourth proportional to 18.15, 27.21 and 13.05 is: 19.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    18.15 : 27.21 = 13.05 : x
  2. Step 2: Convert to fraction form
    18.15/27.21 = 13.05/x
  3. Step 3: Cross multiply
    18.15x = 27.21 × 13.05
  4. Step 4: Simplify right side
    18.15x = 355.09
  5. Step 5: Solve for x
    x = 355.09/18.15
  6. Step 6: Final answer
    x = 19.56

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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.