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Finding the Fourth Proportional to 20.55, 28.29 and 16.20

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Solution

The fourth proportional to 20.55, 28.29 and 16.20 is: 22.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.55 : 28.29 = 16.20 : x
  2. Step 2: Convert to fraction form
    20.55/28.29 = 16.20/x
  3. Step 3: Cross multiply
    20.55x = 28.29 × 16.20
  4. Step 4: Simplify right side
    20.55x = 458.30
  5. Step 5: Solve for x
    x = 458.30/20.55
  6. Step 6: Final answer
    x = 22.30

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.