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Finding the Fourth Proportional to 80.65, 121.12 and 50.42

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Solution

The fourth proportional to 80.65, 121.12 and 50.42 is: 75.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.65 : 121.12 = 50.42 : x
  2. Step 2: Convert to fraction form
    80.65/121.12 = 50.42/x
  3. Step 3: Cross multiply
    80.65x = 121.12 × 50.42
  4. Step 4: Simplify right side
    80.65x = 6,106.62
  5. Step 5: Solve for x
    x = 6,106.62/80.65
  6. Step 6: Final answer
    x = 75.72

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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.