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Finding the Fourth Proportional to 80.10, 120.65 and 72.92

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Solution

The fourth proportional to 80.10, 120.65 and 72.92 is: 109.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.10 : 120.65 = 72.92 : x
  2. Step 2: Convert to fraction form
    80.10/120.65 = 72.92/x
  3. Step 3: Cross multiply
    80.10x = 120.65 × 72.92
  4. Step 4: Simplify right side
    80.10x = 8,798.28
  5. Step 5: Solve for x
    x = 8,798.28/80.10
  6. Step 6: Final answer
    x = 109.84

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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.