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Finding the Fourth Proportional to 379.90, 569.13 and 217.09

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Solution

The fourth proportional to 379.90, 569.13 and 217.09 is: 325.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    379.90 : 569.13 = 217.09 : x
  2. Step 2: Convert to fraction form
    379.90/569.13 = 217.09/x
  3. Step 3: Cross multiply
    379.90x = 569.13 × 217.09
  4. Step 4: Simplify right side
    379.90x = 123,552.43
  5. Step 5: Solve for x
    x = 123,552.43/379.90
  6. Step 6: Final answer
    x = 325.22

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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.