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Finding the Fourth Proportional to 278.91, 417.81 and 213.09

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Solution

The fourth proportional to 278.91, 417.81 and 213.09 is: 319.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.91 : 417.81 = 213.09 : x
  2. Step 2: Convert to fraction form
    278.91/417.81 = 213.09/x
  3. Step 3: Cross multiply
    278.91x = 417.81 × 213.09
  4. Step 4: Simplify right side
    278.91x = 89,032.10
  5. Step 5: Solve for x
    x = 89,032.10/278.91
  6. Step 6: Final answer
    x = 319.22

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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.