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Finding the Fourth Proportional to 80.60, 120.75 and 51.71

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Solution

The fourth proportional to 80.60, 120.75 and 51.71 is: 77.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.60 : 120.75 = 51.71 : x
  2. Step 2: Convert to fraction form
    80.60/120.75 = 51.71/x
  3. Step 3: Cross multiply
    80.60x = 120.75 × 51.71
  4. Step 4: Simplify right side
    80.60x = 6,243.98
  5. Step 5: Solve for x
    x = 6,243.98/80.60
  6. Step 6: Final answer
    x = 77.47

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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.