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Finding the Fourth Proportional to 82.08, 122.79 and 54.90

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Solution

The fourth proportional to 82.08, 122.79 and 54.90 is: 82.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    82.08 : 122.79 = 54.90 : x
  2. Step 2: Convert to fraction form
    82.08/122.79 = 54.90/x
  3. Step 3: Cross multiply
    82.08x = 122.79 × 54.90
  4. Step 4: Simplify right side
    82.08x = 6,741.17
  5. Step 5: Solve for x
    x = 6,741.17/82.08
  6. Step 6: Final answer
    x = 82.13

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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.