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Finding the Fourth Proportional to 54.61, 81.85 and 20.35

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Solution

The fourth proportional to 54.61, 81.85 and 20.35 is: 30.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    54.61 : 81.85 = 20.35 : x
  2. Step 2: Convert to fraction form
    54.61/81.85 = 20.35/x
  3. Step 3: Cross multiply
    54.61x = 81.85 × 20.35
  4. Step 4: Simplify right side
    54.61x = 1,665.29
  5. Step 5: Solve for x
    x = 1,665.29/54.61
  6. Step 6: Final answer
    x = 30.50

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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.