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Finding the Fourth Proportional to 20.19, 30.17 and 16.80

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Solution

The fourth proportional to 20.19, 30.17 and 16.80 is: 25.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.19 : 30.17 = 16.80 : x
  2. Step 2: Convert to fraction form
    20.19/30.17 = 16.80/x
  3. Step 3: Cross multiply
    20.19x = 30.17 × 16.80
  4. Step 4: Simplify right side
    20.19x = 506.77
  5. Step 5: Solve for x
    x = 506.77/20.19
  6. Step 6: Final answer
    x = 25.10

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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.