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Finding the Fourth Proportional to 57.80, 86.21 and 55.58

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Solution

The fourth proportional to 57.80, 86.21 and 55.58 is: 82.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    57.80 : 86.21 = 55.58 : x
  2. Step 2: Convert to fraction form
    57.80/86.21 = 55.58/x
  3. Step 3: Cross multiply
    57.80x = 86.21 × 55.58
  4. Step 4: Simplify right side
    57.80x = 4,790.84
  5. Step 5: Solve for x
    x = 4,790.84/57.80
  6. Step 6: Final answer
    x = 82.89

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.