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Finding the Fourth Proportional to 72.72, 108.87 and 54.40

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Solution

The fourth proportional to 72.72, 108.87 and 54.40 is: 81.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.72 : 108.87 = 54.40 : x
  2. Step 2: Convert to fraction form
    72.72/108.87 = 54.40/x
  3. Step 3: Cross multiply
    72.72x = 108.87 × 54.40
  4. Step 4: Simplify right side
    72.72x = 5,922.53
  5. Step 5: Solve for x
    x = 5,922.53/72.72
  6. Step 6: Final answer
    x = 81.44

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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.