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Finding the Fourth Proportional to 380.78, 570.45 and 217.97

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Solution

The fourth proportional to 380.78, 570.45 and 217.97 is: 326.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.78 : 570.45 = 217.97 : x
  2. Step 2: Convert to fraction form
    380.78/570.45 = 217.97/x
  3. Step 3: Cross multiply
    380.78x = 570.45 × 217.97
  4. Step 4: Simplify right side
    380.78x = 124,338.13
  5. Step 5: Solve for x
    x = 124,338.13/380.78
  6. Step 6: Final answer
    x = 326.54

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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.