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Finding the Fourth Proportional to 381.81, 572.31 and 219.15

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Solution

The fourth proportional to 381.81, 572.31 and 219.15 is: 328.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.81 : 572.31 = 219.15 : x
  2. Step 2: Convert to fraction form
    381.81/572.31 = 219.15/x
  3. Step 3: Cross multiply
    381.81x = 572.31 × 219.15
  4. Step 4: Simplify right side
    381.81x = 125,421.74
  5. Step 5: Solve for x
    x = 125,421.74/381.81
  6. Step 6: Final answer
    x = 328.49

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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.