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Finding the Fourth Proportional to 79.99, 119.85 and 71.89

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Solution

The fourth proportional to 79.99, 119.85 and 71.89 is: 107.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.99 : 119.85 = 71.89 : x
  2. Step 2: Convert to fraction form
    79.99/119.85 = 71.89/x
  3. Step 3: Cross multiply
    79.99x = 119.85 × 71.89
  4. Step 4: Simplify right side
    79.99x = 8,616.02
  5. Step 5: Solve for x
    x = 8,616.02/79.99
  6. Step 6: Final answer
    x = 107.71

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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.