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Finding the Fourth Proportional to 20.91, 28.83 and 18.32

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Solution

The fourth proportional to 20.91, 28.83 and 18.32 is: 25.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.91 : 28.83 = 18.32 : x
  2. Step 2: Convert to fraction form
    20.91/28.83 = 18.32/x
  3. Step 3: Cross multiply
    20.91x = 28.83 × 18.32
  4. Step 4: Simplify right side
    20.91x = 528.02
  5. Step 5: Solve for x
    x = 528.02/20.91
  6. Step 6: Final answer
    x = 25.25

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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.