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Finding the Fourth Proportional to 80.31, 110.84 and 51.21

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Solution

The fourth proportional to 80.31, 110.84 and 51.21 is: 70.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.31 : 110.84 = 51.21 : x
  2. Step 2: Convert to fraction form
    80.31/110.84 = 51.21/x
  3. Step 3: Cross multiply
    80.31x = 110.84 × 51.21
  4. Step 4: Simplify right side
    80.31x = 5,676.12
  5. Step 5: Solve for x
    x = 5,676.12/80.31
  6. Step 6: Final answer
    x = 70.68

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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.