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Finding the Fourth Proportional to 80.75, 111.36 and 53.09

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Solution

The fourth proportional to 80.75, 111.36 and 53.09 is: 73.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.75 : 111.36 = 53.09 : x
  2. Step 2: Convert to fraction form
    80.75/111.36 = 53.09/x
  3. Step 3: Cross multiply
    80.75x = 111.36 × 53.09
  4. Step 4: Simplify right side
    80.75x = 5,912.10
  5. Step 5: Solve for x
    x = 5,912.10/80.75
  6. Step 6: Final answer
    x = 73.21

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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.