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Finding the Fourth Proportional to 393.30, 540.81 and 381.15

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Solution

The fourth proportional to 393.30, 540.81 and 381.15 is: 524.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    393.30 : 540.81 = 381.15 : x
  2. Step 2: Convert to fraction form
    393.30/540.81 = 381.15/x
  3. Step 3: Cross multiply
    393.30x = 540.81 × 381.15
  4. Step 4: Simplify right side
    393.30x = 206,129.73
  5. Step 5: Solve for x
    x = 206,129.73/393.30
  6. Step 6: Final answer
    x = 524.10

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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.