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Finding the Fourth Proportional to 381.00, 571.40 and 218.60

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Solution

The fourth proportional to 381.00, 571.40 and 218.60 is: 327.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.00 : 571.40 = 218.60 : x
  2. Step 2: Convert to fraction form
    381.00/571.40 = 218.60/x
  3. Step 3: Cross multiply
    381.00x = 571.40 × 218.60
  4. Step 4: Simplify right side
    381.00x = 124,908.28
  5. Step 5: Solve for x
    x = 124,908.28/381.00
  6. Step 6: Final answer
    x = 327.84

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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.