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Finding the Fourth Proportional to 80.46, 121.15 and 71.52

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Solution

The fourth proportional to 80.46, 121.15 and 71.52 is: 107.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.46 : 121.15 = 71.52 : x
  2. Step 2: Convert to fraction form
    80.46/121.15 = 71.52/x
  3. Step 3: Cross multiply
    80.46x = 121.15 × 71.52
  4. Step 4: Simplify right side
    80.46x = 8,664.65
  5. Step 5: Solve for x
    x = 8,664.65/80.46
  6. Step 6: Final answer
    x = 107.69

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.