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Finding the Fourth Proportional to 80.38, 119.79 and 79.71

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Solution

The fourth proportional to 80.38, 119.79 and 79.71 is: 118.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.38 : 119.79 = 79.71 : x
  2. Step 2: Convert to fraction form
    80.38/119.79 = 79.71/x
  3. Step 3: Cross multiply
    80.38x = 119.79 × 79.71
  4. Step 4: Simplify right side
    80.38x = 9,548.35
  5. Step 5: Solve for x
    x = 9,548.35/80.38
  6. Step 6: Final answer
    x = 118.79

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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.