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Finding the Fourth Proportional to 80.80, 121.26 and 75.40

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Solution

The fourth proportional to 80.80, 121.26 and 75.40 is: 113.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.80 : 121.26 = 75.40 : x
  2. Step 2: Convert to fraction form
    80.80/121.26 = 75.40/x
  3. Step 3: Cross multiply
    80.80x = 121.26 × 75.40
  4. Step 4: Simplify right side
    80.80x = 9,143.00
  5. Step 5: Solve for x
    x = 9,143.00/80.80
  6. Step 6: Final answer
    x = 113.16

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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.