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Finding the Fourth Proportional to 79.87, 119.04 and 77.70

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Solution

The fourth proportional to 79.87, 119.04 and 77.70 is: 115.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.87 : 119.04 = 77.70 : x
  2. Step 2: Convert to fraction form
    79.87/119.04 = 77.70/x
  3. Step 3: Cross multiply
    79.87x = 119.04 × 77.70
  4. Step 4: Simplify right side
    79.87x = 9,249.41
  5. Step 5: Solve for x
    x = 9,249.41/79.87
  6. Step 6: Final answer
    x = 115.81

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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.