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Finding the Fourth Proportional to 379.92, 569.40 and 217.72

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Solution

The fourth proportional to 379.92, 569.40 and 217.72 is: 326.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    379.92 : 569.40 = 217.72 : x
  2. Step 2: Convert to fraction form
    379.92/569.40 = 217.72/x
  3. Step 3: Cross multiply
    379.92x = 569.40 × 217.72
  4. Step 4: Simplify right side
    379.92x = 123,969.77
  5. Step 5: Solve for x
    x = 123,969.77/379.92
  6. Step 6: Final answer
    x = 326.30

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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.