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Finding the Fourth Proportional to 279.38, 419.31 and 218.90

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Solution

The fourth proportional to 279.38, 419.31 and 218.90 is: 328.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.38 : 419.31 = 218.90 : x
  2. Step 2: Convert to fraction form
    279.38/419.31 = 218.90/x
  3. Step 3: Cross multiply
    279.38x = 419.31 × 218.90
  4. Step 4: Simplify right side
    279.38x = 91,788.01
  5. Step 5: Solve for x
    x = 91,788.01/279.38
  6. Step 6: Final answer
    x = 328.54

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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.