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Finding the Fourth Proportional to 80.76, 121.16 and 58.11

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Solution

The fourth proportional to 80.76, 121.16 and 58.11 is: 87.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.76 : 121.16 = 58.11 : x
  2. Step 2: Convert to fraction form
    80.76/121.16 = 58.11/x
  3. Step 3: Cross multiply
    80.76x = 121.16 × 58.11
  4. Step 4: Simplify right side
    80.76x = 7,040.61
  5. Step 5: Solve for x
    x = 7,040.61/80.76
  6. Step 6: Final answer
    x = 87.18

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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.