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Finding the Fourth Proportional to 427.25, 639.01 and 381.31

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Solution

The fourth proportional to 427.25, 639.01 and 381.31 is: 570.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.25 : 639.01 = 381.31 : x
  2. Step 2: Convert to fraction form
    427.25/639.01 = 381.31/x
  3. Step 3: Cross multiply
    427.25x = 639.01 × 381.31
  4. Step 4: Simplify right side
    427.25x = 243,660.85
  5. Step 5: Solve for x
    x = 243,660.85/427.25
  6. Step 6: Final answer
    x = 570.30

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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.