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Finding the Fourth Proportional to 381.21, 571.29 and 207.42

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Solution

The fourth proportional to 381.21, 571.29 and 207.42 is: 310.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.21 : 571.29 = 207.42 : x
  2. Step 2: Convert to fraction form
    381.21/571.29 = 207.42/x
  3. Step 3: Cross multiply
    381.21x = 571.29 × 207.42
  4. Step 4: Simplify right side
    381.21x = 118,496.97
  5. Step 5: Solve for x
    x = 118,496.97/381.21
  6. Step 6: Final answer
    x = 310.84

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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.