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Finding the Fourth Proportional to 279.21, 385.33 and 154.87

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Solution

The fourth proportional to 279.21, 385.33 and 154.87 is: 213.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.21 : 385.33 = 154.87 : x
  2. Step 2: Convert to fraction form
    279.21/385.33 = 154.87/x
  3. Step 3: Cross multiply
    279.21x = 385.33 × 154.87
  4. Step 4: Simplify right side
    279.21x = 59,676.06
  5. Step 5: Solve for x
    x = 59,676.06/279.21
  6. Step 6: Final answer
    x = 213.73

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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.