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Finding the Fourth Proportional to 34.71, 47.90 and 20.89

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Solution

The fourth proportional to 34.71, 47.90 and 20.89 is: 28.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    34.71 : 47.90 = 20.89 : x
  2. Step 2: Convert to fraction form
    34.71/47.90 = 20.89/x
  3. Step 3: Cross multiply
    34.71x = 47.90 × 20.89
  4. Step 4: Simplify right side
    34.71x = 1,000.74
  5. Step 5: Solve for x
    x = 1,000.74/34.71
  6. Step 6: Final answer
    x = 28.83

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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.