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Finding the Fourth Proportional to 144.75, 217.28 and 79.80

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Solution

The fourth proportional to 144.75, 217.28 and 79.80 is: 119.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    144.75 : 217.28 = 79.80 : x
  2. Step 2: Convert to fraction form
    144.75/217.28 = 79.80/x
  3. Step 3: Cross multiply
    144.75x = 217.28 × 79.80
  4. Step 4: Simplify right side
    144.75x = 17,338.55
  5. Step 5: Solve for x
    x = 17,338.55/144.75
  6. Step 6: Final answer
    x = 119.78

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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.