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Finding the Fourth Proportional to 17.20, 25.69 and 12.85

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Solution

The fourth proportional to 17.20, 25.69 and 12.85 is: 19.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    17.20 : 25.69 = 12.85 : x
  2. Step 2: Convert to fraction form
    17.20/25.69 = 12.85/x
  3. Step 3: Cross multiply
    17.20x = 25.69 × 12.85
  4. Step 4: Simplify right side
    17.20x = 330.12
  5. Step 5: Solve for x
    x = 330.12/17.20
  6. Step 6: Final answer
    x = 19.19

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.