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Finding the Fourth Proportional to 80.40, 119.80 and 77.36

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Solution

The fourth proportional to 80.40, 119.80 and 77.36 is: 115.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.40 : 119.80 = 77.36 : x
  2. Step 2: Convert to fraction form
    80.40/119.80 = 77.36/x
  3. Step 3: Cross multiply
    80.40x = 119.80 × 77.36
  4. Step 4: Simplify right side
    80.40x = 9,267.73
  5. Step 5: Solve for x
    x = 9,267.73/80.40
  6. Step 6: Final answer
    x = 115.27

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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.