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Finding the Fourth Proportional to 54.39, 81.14 and 47.91

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Solution

The fourth proportional to 54.39, 81.14 and 47.91 is: 71.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    54.39 : 81.14 = 47.91 : x
  2. Step 2: Convert to fraction form
    54.39/81.14 = 47.91/x
  3. Step 3: Cross multiply
    54.39x = 81.14 × 47.91
  4. Step 4: Simplify right side
    54.39x = 3,887.18
  5. Step 5: Solve for x
    x = 3,887.18/54.39
  6. Step 6: Final answer
    x = 71.47

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.