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Finding the Fourth Proportional to 54.18, 81.90 and 54.18

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Solution

The fourth proportional to 54.18, 81.90 and 54.18 is: 81.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    54.18 : 81.90 = 54.18 : x
  2. Step 2: Convert to fraction form
    54.18/81.90 = 54.18/x
  3. Step 3: Cross multiply
    54.18x = 81.90 × 54.18
  4. Step 4: Simplify right side
    54.18x = 4,437.34
  5. Step 5: Solve for x
    x = 4,437.34/54.18
  6. Step 6: Final answer
    x = 81.90

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.