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Finding the Fourth Proportional to 13.45, 20.21 and 10.80

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Solution

The fourth proportional to 13.45, 20.21 and 10.80 is: 16.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    13.45 : 20.21 = 10.80 : x
  2. Step 2: Convert to fraction form
    13.45/20.21 = 10.80/x
  3. Step 3: Cross multiply
    13.45x = 20.21 × 10.80
  4. Step 4: Simplify right side
    13.45x = 218.27
  5. Step 5: Solve for x
    x = 218.27/13.45
  6. Step 6: Final answer
    x = 16.23

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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.