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Finding the Fourth Proportional to 80.35, 120.26 and 65.78

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Solution

The fourth proportional to 80.35, 120.26 and 65.78 is: 98.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.35 : 120.26 = 65.78 : x
  2. Step 2: Convert to fraction form
    80.35/120.26 = 65.78/x
  3. Step 3: Cross multiply
    80.35x = 120.26 × 65.78
  4. Step 4: Simplify right side
    80.35x = 7,910.72
  5. Step 5: Solve for x
    x = 7,910.72/80.35
  6. Step 6: Final answer
    x = 98.46

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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.