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Finding the Fourth Proportional to 272.20, 408.16 and 79.80

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Solution

The fourth proportional to 272.20, 408.16 and 79.80 is: 119.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    272.20 : 408.16 = 79.80 : x
  2. Step 2: Convert to fraction form
    272.20/408.16 = 79.80/x
  3. Step 3: Cross multiply
    272.20x = 408.16 × 79.80
  4. Step 4: Simplify right side
    272.20x = 32,571.17
  5. Step 5: Solve for x
    x = 32,571.17/272.20
  6. Step 6: Final answer
    x = 119.66

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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.