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Finding the Fourth Proportional to 279.05, 385.09 and 154.71

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Solution

The fourth proportional to 279.05, 385.09 and 154.71 is: 213.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.05 : 385.09 = 154.71 : x
  2. Step 2: Convert to fraction form
    279.05/385.09 = 154.71/x
  3. Step 3: Cross multiply
    279.05x = 385.09 × 154.71
  4. Step 4: Simplify right side
    279.05x = 59,577.27
  5. Step 5: Solve for x
    x = 59,577.27/279.05
  6. Step 6: Final answer
    x = 213.50

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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.