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Finding the Fourth Proportional to 379.89, 569.90 and 217.76

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Solution

The fourth proportional to 379.89, 569.90 and 217.76 is: 326.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    379.89 : 569.90 = 217.76 : x
  2. Step 2: Convert to fraction form
    379.89/569.90 = 217.76/x
  3. Step 3: Cross multiply
    379.89x = 569.90 × 217.76
  4. Step 4: Simplify right side
    379.89x = 124,099.12
  5. Step 5: Solve for x
    x = 124,099.12/379.89
  6. Step 6: Final answer
    x = 326.67

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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.