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Finding the Fourth Proportional to 57.37, 86.06 and 20.80

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Solution

The fourth proportional to 57.37, 86.06 and 20.80 is: 31.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    57.37 : 86.06 = 20.80 : x
  2. Step 2: Convert to fraction form
    57.37/86.06 = 20.80/x
  3. Step 3: Cross multiply
    57.37x = 86.06 × 20.80
  4. Step 4: Simplify right side
    57.37x = 1,790.05
  5. Step 5: Solve for x
    x = 1,790.05/57.37
  6. Step 6: Final answer
    x = 31.20

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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.