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Finding the Fourth Proportional to 80.73, 111.38 and 64.31

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Solution

The fourth proportional to 80.73, 111.38 and 64.31 is: 88.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.73 : 111.38 = 64.31 : x
  2. Step 2: Convert to fraction form
    80.73/111.38 = 64.31/x
  3. Step 3: Cross multiply
    80.73x = 111.38 × 64.31
  4. Step 4: Simplify right side
    80.73x = 7,161.97
  5. Step 5: Solve for x
    x = 7,161.97/80.73
  6. Step 6: Final answer
    x = 88.72

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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.