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Finding the Fourth Proportional to 279.15, 385.05 and 180.78

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Solution

The fourth proportional to 279.15, 385.05 and 180.78 is: 249.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.15 : 385.05 = 180.78 : x
  2. Step 2: Convert to fraction form
    279.15/385.05 = 180.78/x
  3. Step 3: Cross multiply
    279.15x = 385.05 × 180.78
  4. Step 4: Simplify right side
    279.15x = 69,609.34
  5. Step 5: Solve for x
    x = 69,609.34/279.15
  6. Step 6: Final answer
    x = 249.36

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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.