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Finding the Fourth Proportional to 381.09, 570.71 and 218.28

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Solution

The fourth proportional to 381.09, 570.71 and 218.28 is: 326.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.09 : 570.71 = 218.28 : x
  2. Step 2: Convert to fraction form
    381.09/570.71 = 218.28/x
  3. Step 3: Cross multiply
    381.09x = 570.71 × 218.28
  4. Step 4: Simplify right side
    381.09x = 124,570.63
  5. Step 5: Solve for x
    x = 124,570.63/381.09
  6. Step 6: Final answer
    x = 326.88

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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.