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Finding the Fourth Proportional to 278.05, 417.25 and 217.30

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Solution

The fourth proportional to 278.05, 417.25 and 217.30 is: 326.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.05 : 417.25 = 217.30 : x
  2. Step 2: Convert to fraction form
    278.05/417.25 = 217.30/x
  3. Step 3: Cross multiply
    278.05x = 417.25 × 217.30
  4. Step 4: Simplify right side
    278.05x = 90,668.43
  5. Step 5: Solve for x
    x = 90,668.43/278.05
  6. Step 6: Final answer
    x = 326.09

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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.