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Finding the Fourth Proportional to 80.17, 120.01 and 64.78

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Solution

The fourth proportional to 80.17, 120.01 and 64.78 is: 96.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.17 : 120.01 = 64.78 : x
  2. Step 2: Convert to fraction form
    80.17/120.01 = 64.78/x
  3. Step 3: Cross multiply
    80.17x = 120.01 × 64.78
  4. Step 4: Simplify right side
    80.17x = 7,774.25
  5. Step 5: Solve for x
    x = 7,774.25/80.17
  6. Step 6: Final answer
    x = 96.97

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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.