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Finding the Fourth Proportional to 54.18, 81.19 and 28.45

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Solution

The fourth proportional to 54.18, 81.19 and 28.45 is: 42.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    54.18 : 81.19 = 28.45 : x
  2. Step 2: Convert to fraction form
    54.18/81.19 = 28.45/x
  3. Step 3: Cross multiply
    54.18x = 81.19 × 28.45
  4. Step 4: Simplify right side
    54.18x = 2,309.86
  5. Step 5: Solve for x
    x = 2,309.86/54.18
  6. Step 6: Final answer
    x = 42.63

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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.