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Finding the Fourth Proportional to 38.91, 58.32 and 20.65

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Solution

The fourth proportional to 38.91, 58.32 and 20.65 is: 30.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    38.91 : 58.32 = 20.65 : x
  2. Step 2: Convert to fraction form
    38.91/58.32 = 20.65/x
  3. Step 3: Cross multiply
    38.91x = 58.32 × 20.65
  4. Step 4: Simplify right side
    38.91x = 1,204.11
  5. Step 5: Solve for x
    x = 1,204.11/38.91
  6. Step 6: Final answer
    x = 30.95

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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.