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Finding the Fourth Proportional to 80.70, 120.98 and 26.57

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Solution

The fourth proportional to 80.70, 120.98 and 26.57 is: 39.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.70 : 120.98 = 26.57 : x
  2. Step 2: Convert to fraction form
    80.70/120.98 = 26.57/x
  3. Step 3: Cross multiply
    80.70x = 120.98 × 26.57
  4. Step 4: Simplify right side
    80.70x = 3,213.70
  5. Step 5: Solve for x
    x = 3,213.70/80.70
  6. Step 6: Final answer
    x = 39.82

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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.