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Finding the Fourth Proportional to 54.42, 81.98 and 54.15

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Solution

The fourth proportional to 54.42, 81.98 and 54.15 is: 81.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    54.42 : 81.98 = 54.15 : x
  2. Step 2: Convert to fraction form
    54.42/81.98 = 54.15/x
  3. Step 3: Cross multiply
    54.42x = 81.98 × 54.15
  4. Step 4: Simplify right side
    54.42x = 4,438.95
  5. Step 5: Solve for x
    x = 4,438.95/54.42
  6. Step 6: Final answer
    x = 81.57

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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.