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Finding the Fourth Proportional to 72.05, 107.80 and 39.83

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Solution

The fourth proportional to 72.05, 107.80 and 39.83 is: 59.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.05 : 107.80 = 39.83 : x
  2. Step 2: Convert to fraction form
    72.05/107.80 = 39.83/x
  3. Step 3: Cross multiply
    72.05x = 107.80 × 39.83
  4. Step 4: Simplify right side
    72.05x = 4,293.67
  5. Step 5: Solve for x
    x = 4,293.67/72.05
  6. Step 6: Final answer
    x = 59.59

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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.