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Finding the Fourth Proportional to 279.36, 385.14 and 213.78

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Solution

The fourth proportional to 279.36, 385.14 and 213.78 is: 294.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.36 : 385.14 = 213.78 : x
  2. Step 2: Convert to fraction form
    279.36/385.14 = 213.78/x
  3. Step 3: Cross multiply
    279.36x = 385.14 × 213.78
  4. Step 4: Simplify right side
    279.36x = 82,335.23
  5. Step 5: Solve for x
    x = 82,335.23/279.36
  6. Step 6: Final answer
    x = 294.73

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.