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Finding the Fourth Proportional to 26.80, 40.17 and 20.81

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Solution

The fourth proportional to 26.80, 40.17 and 20.81 is: 31.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    26.80 : 40.17 = 20.81 : x
  2. Step 2: Convert to fraction form
    26.80/40.17 = 20.81/x
  3. Step 3: Cross multiply
    26.80x = 40.17 × 20.81
  4. Step 4: Simplify right side
    26.80x = 835.94
  5. Step 5: Solve for x
    x = 835.94/26.80
  6. Step 6: Final answer
    x = 31.20

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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.