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Finding the Fourth Proportional to 80.86, 121.43 and 58.05

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Solution

The fourth proportional to 80.86, 121.43 and 58.05 is: 87.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.86 : 121.43 = 58.05 : x
  2. Step 2: Convert to fraction form
    80.86/121.43 = 58.05/x
  3. Step 3: Cross multiply
    80.86x = 121.43 × 58.05
  4. Step 4: Simplify right side
    80.86x = 7,049.01
  5. Step 5: Solve for x
    x = 7,049.01/80.86
  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.