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Finding the Fourth Proportional to 381.48, 571.80 and 219.20

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Solution

The fourth proportional to 381.48, 571.80 and 219.20 is: 328.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.48 : 571.80 = 219.20 : x
  2. Step 2: Convert to fraction form
    381.48/571.80 = 219.20/x
  3. Step 3: Cross multiply
    381.48x = 571.80 × 219.20
  4. Step 4: Simplify right side
    381.48x = 125,338.56
  5. Step 5: Solve for x
    x = 125,338.56/381.48
  6. Step 6: Final answer
    x = 328.56

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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.