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Finding the Fourth Proportional to 17.21, 25.81 and 5.18

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Solution

The fourth proportional to 17.21, 25.81 and 5.18 is: 7.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    17.21 : 25.81 = 5.18 : x
  2. Step 2: Convert to fraction form
    17.21/25.81 = 5.18/x
  3. Step 3: Cross multiply
    17.21x = 25.81 × 5.18
  4. Step 4: Simplify right side
    17.21x = 133.75
  5. Step 5: Solve for x
    x = 133.75/17.21
  6. Step 6: Final answer
    x = 7.77

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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.