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Finding the Fourth Proportional to 81.10, 112.02 and 76.54

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Solution

The fourth proportional to 81.10, 112.02 and 76.54 is: 105.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    81.10 : 112.02 = 76.54 : x
  2. Step 2: Convert to fraction form
    81.10/112.02 = 76.54/x
  3. Step 3: Cross multiply
    81.10x = 112.02 × 76.54
  4. Step 4: Simplify right side
    81.10x = 8,574.01
  5. Step 5: Solve for x
    x = 8,574.01/81.10
  6. Step 6: Final answer
    x = 105.72

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.