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Finding the Fourth Proportional to 275.53, 380.28 and 217.21

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Solution

The fourth proportional to 275.53, 380.28 and 217.21 is: 299.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    275.53 : 380.28 = 217.21 : x
  2. Step 2: Convert to fraction form
    275.53/380.28 = 217.21/x
  3. Step 3: Cross multiply
    275.53x = 380.28 × 217.21
  4. Step 4: Simplify right side
    275.53x = 82,600.62
  5. Step 5: Solve for x
    x = 82,600.62/275.53
  6. Step 6: Final answer
    x = 299.79

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.