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Finding the Fourth Proportional to 47.87, 71.82 and 19.39

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Solution

The fourth proportional to 47.87, 71.82 and 19.39 is: 29.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    47.87 : 71.82 = 19.39 : x
  2. Step 2: Convert to fraction form
    47.87/71.82 = 19.39/x
  3. Step 3: Cross multiply
    47.87x = 71.82 × 19.39
  4. Step 4: Simplify right side
    47.87x = 1,392.18
  5. Step 5: Solve for x
    x = 1,392.18/47.87
  6. Step 6: Final answer
    x = 29.09

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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.