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Finding the Fourth Proportional to 82.05, 123.19 and 72.50

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Solution

The fourth proportional to 82.05, 123.19 and 72.50 is: 108.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    82.05 : 123.19 = 72.50 : x
  2. Step 2: Convert to fraction form
    82.05/123.19 = 72.50/x
  3. Step 3: Cross multiply
    82.05x = 123.19 × 72.50
  4. Step 4: Simplify right side
    82.05x = 8,930.66
  5. Step 5: Solve for x
    x = 8,930.66/82.05
  6. Step 6: Final answer
    x = 108.85

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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.